plpgsql - DECLARE - cannot to use %TYPE or %ROWTYPE for composite types

commit 76d258edf9ef8e9645f47645a18d79f0d4245d41
Author: Pavel Stehule <pavel.stehule@gooddata.com>
Date:   Fri Oct 30 11:48:33 2015 +0100

    enhancing referenced types - possibility to get array or element type of referenced variable type.
    row variables and row values are supported now too.

diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
index 1ae4bb7..333d2bc 100644
--- a/src/pl/plpgsql/src/pl_comp.c
+++ b/src/pl/plpgsql/src/pl_comp.c
@@ -1617,6 +1617,62 @@ plpgsql_parse_tripword(char *word1, char *word2, char *word3,
 	return false;
 }
 
+/*
+ * Derive type from ny base type controlled by reftype_mode
+ *
+ */
+static PLpgSQL_type *
+derive_type(PLpgSQL_type *base_type, int reftype_mode)
+{
+	Oid typoid;
+
+	switch (reftype_mode)
+	{
+		case PLPGSQL_REFTYPE_TYPE:
+			return base_type;
+
+		case PLPGSQL_REFTYPE_ELEMENT:
+		{
+			typoid = get_element_type(base_type->typoid);
+			if (!OidIsValid(typoid))
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("referenced variable should be an array, not type %s",
+								format_type_be(base_type->typoid))));
+
+			return plpgsql_build_datatype(typoid, -1,
+							plpgsql_curr_compile->fn_input_collation);
+		}
+
+		case PLPGSQL_REFTYPE_ARRAY:
+		{
+			/*
+			 * Question: can we allow anyelement (array or nonarray) -> array direction.
+			 * if yes, then probably we have to modify enforce_generic_type_consistency,
+			 * parse_coerce.c where still is check on scalar type -> raise error
+			 * ERROR:  42704: could not find array type for data type integer[]
+			 *
+			if (OidIsValid(get_element_type(base_type->typoid)))
+				return base_type;
+			*/
+
+			typoid = get_array_type(base_type->typoid);
+			if (!OidIsValid(typoid))
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("there are not array type for type %s",
+									format_type_be(base_type->typoid))));
+
+			return plpgsql_build_datatype(typoid, -1,
+							plpgsql_curr_compile->fn_input_collation);
+		}
+
+		default:
+			return NULL;
+	}
+}
+
+
 
 /* ----------
  * plpgsql_parse_wordtype	The scanner found word%TYPE. word can be
@@ -1626,7 +1682,7 @@ plpgsql_parse_tripword(char *word1, char *word2, char *word3,
  * ----------
  */
 PLpgSQL_type *
-plpgsql_parse_wordtype(char *ident)
+plpgsql_parse_wordtype(char *ident, int reftype_mode)
 {
 	PLpgSQL_type *dtype;
 	PLpgSQL_nsitem *nse;
@@ -1644,10 +1700,23 @@ plpgsql_parse_wordtype(char *ident)
 		switch (nse->itemtype)
 		{
 			case PLPGSQL_NSTYPE_VAR:
-				return ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
+			{
+				dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
+				return derive_type(dtype, reftype_mode);
+			}
 
-				/* XXX perhaps allow REC/ROW here? */
+			case PLPGSQL_NSTYPE_ROW:
+			{
+				dtype = ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
+				return derive_type(dtype, reftype_mode);
+			}
 
+			/*
+			 * XXX perhaps allow REC here? Probably it has not any sense, because
+			 * in this moment, because PLpgSQL doesn't support rec parameters, so
+			 * there should not be any rec polymorphic parameter, and any work can
+			 * be done inside function.
+			 */
 			default:
 				return NULL;
 		}
@@ -1689,7 +1758,7 @@ plpgsql_parse_wordtype(char *ident)
  * ----------
  */
 PLpgSQL_type *
-plpgsql_parse_cwordtype(List *idents)
+plpgsql_parse_cwordtype(List *idents, int reftype_mode)
 {
 	PLpgSQL_type *dtype = NULL;
 	PLpgSQL_nsitem *nse;
@@ -1718,10 +1787,24 @@ plpgsql_parse_cwordtype(List *idents)
 								NULL,
 								NULL);
 
-		if (nse != NULL && nse->itemtype == PLPGSQL_NSTYPE_VAR)
+		if (nse != NULL)
 		{
-			dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
-			goto done;
+			PLpgSQL_type *ref_type;
+
+			if (nse->itemtype == PLPGSQL_NSTYPE_VAR)
+			{
+				ref_type = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
+				dtype = derive_type(ref_type, reftype_mode);
+
+				goto done;
+			}
+			else if (nse->itemtype == PLPGSQL_NSTYPE_ROW)
+			{
+				ref_type = ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
+				dtype = derive_type(ref_type, reftype_mode);
+
+				goto done;
+			}
 		}
 
 		/*
@@ -1903,6 +1986,7 @@ plpgsql_build_variable(const char *refname, int lineno, PLpgSQL_type *dtype,
 				row->dtype = PLPGSQL_DTYPE_ROW;
 				row->refname = pstrdup(refname);
 				row->lineno = lineno;
+				row->datatype = dtype;
 
 				plpgsql_adddatum((PLpgSQL_datum *) row);
 				if (add2namespace)
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
index 841a8d6..a9f87d7 100644
--- a/src/pl/plpgsql/src/pl_gram.y
+++ b/src/pl/plpgsql/src/pl_gram.y
@@ -248,6 +248,7 @@ static	void			check_raise_parameters(PLpgSQL_stmt_raise *stmt);
 %token <keyword>	K_ALIAS
 %token <keyword>	K_ALL
 %token <keyword>	K_ARRAY
+%token <keyword>	K_ARRAYTYPE
 %token <keyword>	K_ASSERT
 %token <keyword>	K_BACKWARD
 %token <keyword>	K_BEGIN
@@ -270,6 +271,7 @@ static	void			check_raise_parameters(PLpgSQL_stmt_raise *stmt);
 %token <keyword>	K_DETAIL
 %token <keyword>	K_DIAGNOSTICS
 %token <keyword>	K_DUMP
+%token <keyword>	K_ELEMENTTYPE
 %token <keyword>	K_ELSE
 %token <keyword>	K_ELSIF
 %token <keyword>	K_END
@@ -2390,6 +2392,7 @@ unreserved_keyword	:
 				K_ABSOLUTE
 				| K_ALIAS
 				| K_ARRAY
+				| K_ARRAYTYPE
 				| K_ASSERT
 				| K_BACKWARD
 				| K_CLOSE
@@ -2408,6 +2411,7 @@ unreserved_keyword	:
 				| K_DETAIL
 				| K_DIAGNOSTICS
 				| K_DUMP
+				| K_ELEMENTTYPE
 				| K_ELSIF
 				| K_ERRCODE
 				| K_ERROR
@@ -2703,8 +2707,8 @@ read_datatype(int tok)
 	startlocation = yylloc;
 
 	/*
-	 * If we have a simple or composite identifier, check for %TYPE
-	 * and %ROWTYPE constructs.
+	 * If we have a simple or composite identifier, check for %TYPE,
+	 * %ELEMENTTYPE, %ARRAYTYPE and %ROWTYPE constructs.
 	 */
 	if (tok == T_WORD)
 	{
@@ -2717,7 +2721,21 @@ read_datatype(int tok)
 			if (tok_is_keyword(tok, &yylval,
 							   K_TYPE, "type"))
 			{
-				result = plpgsql_parse_wordtype(dtname);
+				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_TYPE);
+				if (result)
+					return result;
+			}
+			if (tok_is_keyword(tok, &yylval,
+							   K_ELEMENTTYPE, "elementtype"))
+			{
+				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ELEMENT);
+				if (result)
+					return result;
+			}
+			if (tok_is_keyword(tok, &yylval,
+							   K_ARRAYTYPE, "arraytype"))
+			{
+				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ARRAY);
 				if (result)
 					return result;
 			}
@@ -2741,7 +2759,21 @@ read_datatype(int tok)
 			if (tok_is_keyword(tok, &yylval,
 							   K_TYPE, "type"))
 			{
-				result = plpgsql_parse_wordtype(dtname);
+				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_TYPE);
+				if (result)
+					return result;
+			}
+			if (tok_is_keyword(tok, &yylval,
+							   K_ELEMENTTYPE, "elementtype"))
+			{
+				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ELEMENT);
+				if (result)
+					return result;
+			}
+			if (tok_is_keyword(tok, &yylval,
+							   K_ARRAYTYPE, "arraytype"))
+			{
+				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ARRAY);
 				if (result)
 					return result;
 			}
@@ -2765,7 +2797,21 @@ read_datatype(int tok)
 			if (tok_is_keyword(tok, &yylval,
 							   K_TYPE, "type"))
 			{
-				result = plpgsql_parse_cwordtype(dtnames);
+				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_TYPE);
+				if (result)
+					return result;
+			}
+			if (tok_is_keyword(tok, &yylval,
+							   K_ELEMENTTYPE, "elementtype"))
+			{
+				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_ELEMENT);
+				if (result)
+					return result;
+			}
+			if (tok_is_keyword(tok, &yylval,
+							   K_ARRAYTYPE, "arraytype"))
+			{
+				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_ARRAY);
 				if (result)
 					return result;
 			}
diff --git a/src/pl/plpgsql/src/pl_scanner.c b/src/pl/plpgsql/src/pl_scanner.c
index 683fdab..6e34605 100644
--- a/src/pl/plpgsql/src/pl_scanner.c
+++ b/src/pl/plpgsql/src/pl_scanner.c
@@ -98,6 +98,7 @@ static const ScanKeyword unreserved_keywords[] = {
 	PG_KEYWORD("absolute", K_ABSOLUTE, UNRESERVED_KEYWORD)
 	PG_KEYWORD("alias", K_ALIAS, UNRESERVED_KEYWORD)
 	PG_KEYWORD("array", K_ARRAY, UNRESERVED_KEYWORD)
+	PG_KEYWORD("arraytype", K_ARRAYTYPE, UNRESERVED_KEYWORD)
 	PG_KEYWORD("assert", K_ASSERT, UNRESERVED_KEYWORD)
 	PG_KEYWORD("backward", K_BACKWARD, UNRESERVED_KEYWORD)
 	PG_KEYWORD("close", K_CLOSE, UNRESERVED_KEYWORD)
@@ -116,6 +117,7 @@ static const ScanKeyword unreserved_keywords[] = {
 	PG_KEYWORD("detail", K_DETAIL, UNRESERVED_KEYWORD)
 	PG_KEYWORD("diagnostics", K_DIAGNOSTICS, UNRESERVED_KEYWORD)
 	PG_KEYWORD("dump", K_DUMP, UNRESERVED_KEYWORD)
+	PG_KEYWORD("elementtype", K_ELEMENTTYPE, UNRESERVED_KEYWORD)
 	PG_KEYWORD("elseif", K_ELSIF, UNRESERVED_KEYWORD)
 	PG_KEYWORD("elsif", K_ELSIF, UNRESERVED_KEYWORD)
 	PG_KEYWORD("errcode", K_ERRCODE, UNRESERVED_KEYWORD)
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index 696fb61..5b1a074 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -84,6 +84,17 @@ enum
 };
 
 /* ----------
+ * Possible modes for type references
+ * ----------
+ */
+enum
+{
+	PLPGSQL_REFTYPE_TYPE,		/* use type of some variable */
+	PLPGSQL_REFTYPE_ELEMENT,	/* use a element type of referenced variable */
+	PLPGSQL_REFTYPE_ARRAY		/* use a array type of referenced variable */
+};
+
+/* ----------
  * Execution tree node types
  * ----------
  */
@@ -281,6 +292,7 @@ typedef struct
 	char	   *refname;
 	int			lineno;
 
+	PLpgSQL_type *datatype;
 	TupleDesc	rowtupdesc;
 
 	/*
@@ -961,8 +973,8 @@ extern bool plpgsql_parse_dblword(char *word1, char *word2,
 					  PLwdatum *wdatum, PLcword *cword);
 extern bool plpgsql_parse_tripword(char *word1, char *word2, char *word3,
 					   PLwdatum *wdatum, PLcword *cword);
-extern PLpgSQL_type *plpgsql_parse_wordtype(char *ident);
-extern PLpgSQL_type *plpgsql_parse_cwordtype(List *idents);
+extern PLpgSQL_type *plpgsql_parse_wordtype(char *ident, int reftype_mode);
+extern PLpgSQL_type *plpgsql_parse_cwordtype(List *idents, int reftype_mode);
 extern PLpgSQL_type *plpgsql_parse_wordrowtype(char *ident);
 extern PLpgSQL_type *plpgsql_parse_cwordrowtype(List *idents);
 extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod,
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index e30c579..b6e848b 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -5573,3 +5573,95 @@ end;
 $$;
 ERROR:  unhandled assertion
 CONTEXT:  PL/pgSQL function inline_code_block line 3 at ASSERT
+-- test referenced types
+create type test_composite_type as (x int, y int);
+create or replace function test_simple(src anyelement)
+returns anyelement as $$
+declare dest src%type;
+begin
+  dest := src;
+  return dest;
+end;
+$$ language plpgsql;
+select test_simple(10);
+ test_simple 
+-------------
+          10
+(1 row)
+
+select test_simple('hoj'::text);
+ test_simple 
+-------------
+ hoj
+(1 row)
+
+select test_simple((10,20)::test_composite_type);
+ test_simple 
+-------------
+ (10,20)
+(1 row)
+
+create or replace function test_poly_element(x anyelement)
+returns anyarray as $$
+declare result x%arraytype;
+begin
+  result := ARRAY[x];
+  raise notice '% %', pg_typeof(result), result;
+  return result;
+end;
+$$ language plpgsql;
+select test_poly_element(1);
+NOTICE:  integer[] {1}
+ test_poly_element 
+-------------------
+ {1}
+(1 row)
+
+select test_poly_element('hoj'::text);
+NOTICE:  text[] {hoj}
+ test_poly_element 
+-------------------
+ {hoj}
+(1 row)
+
+select test_poly_element((10,20)::test_composite_type);
+NOTICE:  test_composite_type[] {"(10,20)"}
+ test_poly_element 
+-------------------
+ {"(10,20)"}
+(1 row)
+
+create or replace function test_poly_array(x anyarray)
+returns anyelement as $$
+declare result x%elementtype;
+begin
+  result := x[1];
+  raise notice '% %', pg_typeof(result), result;
+  return result;
+end;
+$$ language plpgsql;
+select test_poly_array(ARRAY[1]);
+NOTICE:  integer 1
+ test_poly_array 
+-----------------
+               1
+(1 row)
+
+select test_poly_array(ARRAY['hoj'::text]);
+NOTICE:  text hoj
+ test_poly_array 
+-----------------
+ hoj
+(1 row)
+
+select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+NOTICE:  test_composite_type (10,20)
+ test_poly_array 
+-----------------
+ (10,20)
+(1 row)
+
+drop function test_simple(anyelement);
+drop type test_composite_type;
+drop function test_poly_element(anyelement);
+drop function test_poly_array(anyarray);
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 7ffef89..46bad10 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -4386,3 +4386,52 @@ exception when others then
   null; -- do nothing
 end;
 $$;
+
+-- test referenced types
+create type test_composite_type as (x int, y int);
+
+create or replace function test_simple(src anyelement)
+returns anyelement as $$
+declare dest src%type;
+begin
+  dest := src;
+  return dest;
+end;
+$$ language plpgsql;
+
+select test_simple(10);
+select test_simple('hoj'::text);
+select test_simple((10,20)::test_composite_type);
+
+create or replace function test_poly_element(x anyelement)
+returns anyarray as $$
+declare result x%arraytype;
+begin
+  result := ARRAY[x];
+  raise notice '% %', pg_typeof(result), result;
+  return result;
+end;
+$$ language plpgsql;
+
+select test_poly_element(1);
+select test_poly_element('hoj'::text);
+select test_poly_element((10,20)::test_composite_type);
+
+create or replace function test_poly_array(x anyarray)
+returns anyelement as $$
+declare result x%elementtype;
+begin
+  result := x[1];
+  raise notice '% %', pg_typeof(result), result;
+  return result;
+end;
+$$ language plpgsql;
+
+select test_poly_array(ARRAY[1]);
+select test_poly_array(ARRAY['hoj'::text]);
+select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+
+drop function test_simple(anyelement);
+drop type test_composite_type;
+drop function test_poly_element(anyelement);
+drop function test_poly_array(anyarray);

*** a/doc/src/sgml/plpgsql.sgml
--- b/doc/src/sgml/plpgsql.sgml
***************
*** 710,715 **** SELECT merge_fields(t.*) FROM table1 t WHERE ... ;
--- 710,756 ----
     </para>
    </sect2>
  
+   <sect2 id="plpgsql-declaration-arraytype">
+    <title>Array Types</title>
+ 
+ <synopsis>
+ <replaceable>variable</replaceable>%ARRAYTYPE
+ </synopsis>
+ 
+    <para>
+     <literal>%ARRAYTYPE</literal> provides the array type from a variable or
+     table column.  You can use this to declare array variables that will
+     hold database values.  To declare an array variable that will hold
+     values from <literal>users.user_id</> you can write:
+ <programlisting>
+ user_id users.user_id%ARRAYTYPE;
+ </programlisting>
+    </para>
+ 
+    <para>
+     By using <literal>%ARRAYTYPE</literal> you don't need to know the data
+     type of elements you are referencing.
+    </para>
+   </sect2>
+ 
+   <sect2 id="plpgsql-declaration-elementtype">
+    <title>Array Element Types</title>
+ 
+ <synopsis>
+ <replaceable>variable</replaceable>%ELEMENTTYPE
+ </synopsis>
+ 
+    <para>
+     <literal>%ELEMENTTYPE</literal> provides the element type of a given
+     array.  To declare a variable with the same data type as
+     <literal>users</> array element you can write:
+ <programlisting>
+ user_id users%ELEMENTTYPE;
+ </programlisting>
+    </para>
+ 
+   </sect2>
+ 
    <sect2 id="plpgsql-declaration-collation">
     <title>Collation of <application>PL/pgSQL</application> Variables</title>
  
*** a/src/pl/plpgsql/src/pl_comp.c
--- b/src/pl/plpgsql/src/pl_comp.c
***************
*** 1619,1625 **** plpgsql_parse_tripword(char *word1, char *word2, char *word3,
  
  /*
   * Derive type from ny base type controlled by reftype_mode
-  *
   */
  static PLpgSQL_type *
  derive_type(PLpgSQL_type *base_type, int reftype_mode)
--- 1619,1624 ----
***************
*** 1661,1667 **** derive_type(PLpgSQL_type *base_type, int reftype_mode)
  				ereport(ERROR,
  						(errcode(ERRCODE_DATATYPE_MISMATCH),
  						 errmsg("there are not array type for type %s",
! 									format_type_be(base_type->typoid))));
  
  			return plpgsql_build_datatype(typoid, -1,
  							plpgsql_curr_compile->fn_input_collation);
--- 1660,1666 ----
  				ereport(ERROR,
  						(errcode(ERRCODE_DATATYPE_MISMATCH),
  						 errmsg("there are not array type for type %s",
! 								format_type_be(base_type->typoid))));
  
  			return plpgsql_build_datatype(typoid, -1,
  							plpgsql_curr_compile->fn_input_collation);
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
***************
*** 2694,2700 **** read_datatype(int tok)
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result;
  	int					parenlevel = 0;
  
  	/* Should only be called while parsing DECLARE sections */
--- 2694,2700 ----
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result = 0;
  	int					parenlevel = 0;
  
  	/* Should only be called while parsing DECLARE sections */
***************
*** 2720,2751 **** read_datatype(int tok)
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
- 			{
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_TYPE);
! 				if (result)
! 					return result;
! 			}
! 			if (tok_is_keyword(tok, &yylval,
! 							   K_ELEMENTTYPE, "elementtype"))
! 			{
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 				if (result)
! 					return result;
! 			}
! 			if (tok_is_keyword(tok, &yylval,
! 							   K_ARRAYTYPE, "arraytype"))
! 			{
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ARRAY);
- 				if (result)
- 					return result;
- 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
--- 2720,2737 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_wordrowtype(dtname);
! 			if (result)
! 				return result;
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
***************
*** 2758,2789 **** read_datatype(int tok)
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
- 			{
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_TYPE);
! 				if (result)
! 					return result;
! 			}
! 			if (tok_is_keyword(tok, &yylval,
! 							   K_ELEMENTTYPE, "elementtype"))
! 			{
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 				if (result)
! 					return result;
! 			}
! 			if (tok_is_keyword(tok, &yylval,
! 							   K_ARRAYTYPE, "arraytype"))
! 			{
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ARRAY);
- 				if (result)
- 					return result;
- 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  	else if (tok == T_CWORD)
--- 2744,2761 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
  				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_wordrowtype(dtname);
! 			if (result)
! 				return result;
  		}
  	}
  	else if (tok == T_CWORD)
***************
*** 2796,2827 **** read_datatype(int tok)
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
- 			{
  				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_TYPE);
! 				if (result)
! 					return result;
! 			}
! 			if (tok_is_keyword(tok, &yylval,
! 							   K_ELEMENTTYPE, "elementtype"))
! 			{
  				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_ELEMENT);
! 				if (result)
! 					return result;
! 			}
! 			if (tok_is_keyword(tok, &yylval,
! 							   K_ARRAYTYPE, "arraytype"))
! 			{
  				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_ARRAY);
- 				if (result)
- 					return result;
- 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  
--- 2768,2785 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
  				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
  				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
  				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 			if (result)
! 				return result;
  		}
  	}
  

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
new file mode 100644
index 9786242..140c81f
*** a/doc/src/sgml/plpgsql.sgml
--- b/doc/src/sgml/plpgsql.sgml
*************** SELECT merge_fields(t.*) FROM table1 t W
*** 710,715 ****
--- 710,792 ----
     </para>
    </sect2>
  
+   <sect2 id="plpgsql-declaration-arraytype">
+    <title>Array Types</title>
+ 
+ <synopsis>
+ <replaceable>variable</replaceable>%ARRAYTYPE
+ </synopsis>
+ 
+    <para>
+     <literal>%ARRAYTYPE</literal> provides the array type from a variable or
+     table column. <literal>%ARRAYTYPE</literal> is particularly valuable in
+     polymorphic functions, since the data types needed for internal variables can
+     change from one call to the next.  Appropriate variables can be
+     created by applying <literal>%ARRAYTYPE</literal> to the function's
+     arguments or result placeholders:
+ <programlisting>
+ CREATE OR REPLACE FUNCTION array_init(v anyelement, size integer)
+ RETURNS anyarray AS $$
+ DECLARE
+     result v%ARRAYTYPE DEFAULT '{}';
+ BEGIN
+     -- prefer builtin function array_fill
+     FOR i IN 1 .. size
+     LOOP
+         result := result || v;
+     END LOOP;
+     RETURN result;
+ END;
+ $$ LANGUAGE plpgsql;
+ 
+ SELECT array_init(0::numeric, 10);
+ SELECT array_init(''::varchar, 10);
+ </programlisting>
+    </para>
+   </sect2>
+ 
+   <sect2 id="plpgsql-declaration-elementtype">
+    <title>Array Element Types</title>
+ 
+ <synopsis>
+ <replaceable>variable</replaceable>%ELEMENTTYPE
+ </synopsis>
+ 
+    <para>
+     <literal>%ELEMENTTYPE</literal> provides the element type of a given
+     array.  <literal>%ELEMENTTYPE</literal> is particularly valuable in polymorphic
+     functions, since the data types needed for internal variables can
+     change from one call to the next.  Appropriate variables can be
+     created by applying <literal>%ELEMENTTYPE</literal> to the function's
+     arguments or result placeholders:
+ <programlisting>
+ CREATE OR REPLACE FUNCTION bubble_sort(a anyarray)
+ RETURNS anyarray AS $$
+ DECLARE
+     aux a%ELEMENTTYPE;
+     repeat_again boolean DEFAULT true;
+ BEGIN
+     -- Don't use this code for large arrays!
+     -- use builtin sort
+     WHILE repeat_again
+     LOOP
+         repeat_again := false;
+         FOR i IN array_lower(a, 1) .. array_upper(a, 1)
+         LOOP
+             IF a[i] > a[i+1] THEN
+                 aux := a[i+1];
+                 a[i+1] := a[i]; a[i] := aux;
+                 repeat_again := true;
+             END IF;
+         END LOOP;
+     END LOOP;
+     RETURN a;
+ END;
+ $$ LANGUAGE plpgsql;
+ </programlisting>
+    </para>
+   </sect2>
+ 
    <sect2 id="plpgsql-declaration-collation">
     <title>Collation of <application>PL/pgSQL</application> Variables</title>
  
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
new file mode 100644
index 1ae4bb7..c819517
*** a/src/pl/plpgsql/src/pl_comp.c
--- b/src/pl/plpgsql/src/pl_comp.c
*************** plpgsql_parse_tripword(char *word1, char
*** 1617,1622 ****
--- 1617,1677 ----
  	return false;
  }
  
+ /*
+  * Derive type from ny base type controlled by reftype_mode
+  */
+ static PLpgSQL_type *
+ derive_type(PLpgSQL_type *base_type, int reftype_mode)
+ {
+ 	Oid typoid;
+ 
+ 	switch (reftype_mode)
+ 	{
+ 		case PLPGSQL_REFTYPE_TYPE:
+ 			return base_type;
+ 
+ 		case PLPGSQL_REFTYPE_ELEMENT:
+ 		{
+ 			typoid = get_element_type(base_type->typoid);
+ 			if (!OidIsValid(typoid))
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_DATATYPE_MISMATCH),
+ 						 errmsg("referenced variable should be an array, not type %s",
+ 								format_type_be(base_type->typoid))));
+ 
+ 			return plpgsql_build_datatype(typoid, -1,
+ 							plpgsql_curr_compile->fn_input_collation);
+ 		}
+ 
+ 		case PLPGSQL_REFTYPE_ARRAY:
+ 		{
+ 			/*
+ 			 * Question: can we allow anyelement (array or nonarray) -> array direction.
+ 			 * if yes, then probably we have to modify enforce_generic_type_consistency,
+ 			 * parse_coerce.c where still is check on scalar type -> raise error
+ 			 * ERROR:  42704: could not find array type for data type integer[]
+ 			 *
+ 			if (OidIsValid(get_element_type(base_type->typoid)))
+ 				return base_type;
+ 			*/
+ 
+ 			typoid = get_array_type(base_type->typoid);
+ 			if (!OidIsValid(typoid))
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_DATATYPE_MISMATCH),
+ 						 errmsg("there are not array type for type %s",
+ 								format_type_be(base_type->typoid))));
+ 
+ 			return plpgsql_build_datatype(typoid, -1,
+ 							plpgsql_curr_compile->fn_input_collation);
+ 		}
+ 
+ 		default:
+ 			return NULL;
+ 	}
+ }
+ 
+ 
  
  /* ----------
   * plpgsql_parse_wordtype	The scanner found word%TYPE. word can be
*************** plpgsql_parse_tripword(char *word1, char
*** 1626,1632 ****
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_wordtype(char *ident)
  {
  	PLpgSQL_type *dtype;
  	PLpgSQL_nsitem *nse;
--- 1681,1687 ----
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_wordtype(char *ident, int reftype_mode)
  {
  	PLpgSQL_type *dtype;
  	PLpgSQL_nsitem *nse;
*************** plpgsql_parse_wordtype(char *ident)
*** 1644,1653 ****
  		switch (nse->itemtype)
  		{
  			case PLPGSQL_NSTYPE_VAR:
! 				return ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
  
! 				/* XXX perhaps allow REC/ROW here? */
  
  			default:
  				return NULL;
  		}
--- 1699,1721 ----
  		switch (nse->itemtype)
  		{
  			case PLPGSQL_NSTYPE_VAR:
! 			{
! 				dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				return derive_type(dtype, reftype_mode);
! 			}
  
! 			case PLPGSQL_NSTYPE_ROW:
! 			{
! 				dtype = ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				return derive_type(dtype, reftype_mode);
! 			}
  
+ 			/*
+ 			 * XXX perhaps allow REC here? Probably it has not any sense, because
+ 			 * in this moment, because PLpgSQL doesn't support rec parameters, so
+ 			 * there should not be any rec polymorphic parameter, and any work can
+ 			 * be done inside function.
+ 			 */
  			default:
  				return NULL;
  		}
*************** plpgsql_parse_wordtype(char *ident)
*** 1689,1695 ****
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_cwordtype(List *idents)
  {
  	PLpgSQL_type *dtype = NULL;
  	PLpgSQL_nsitem *nse;
--- 1757,1763 ----
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_cwordtype(List *idents, int reftype_mode)
  {
  	PLpgSQL_type *dtype = NULL;
  	PLpgSQL_nsitem *nse;
*************** plpgsql_parse_cwordtype(List *idents)
*** 1718,1727 ****
  								NULL,
  								NULL);
  
! 		if (nse != NULL && nse->itemtype == PLPGSQL_NSTYPE_VAR)
  		{
! 			dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 			goto done;
  		}
  
  		/*
--- 1786,1809 ----
  								NULL,
  								NULL);
  
! 		if (nse != NULL)
  		{
! 			PLpgSQL_type *ref_type;
! 
! 			if (nse->itemtype == PLPGSQL_NSTYPE_VAR)
! 			{
! 				ref_type = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				dtype = derive_type(ref_type, reftype_mode);
! 
! 				goto done;
! 			}
! 			else if (nse->itemtype == PLPGSQL_NSTYPE_ROW)
! 			{
! 				ref_type = ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				dtype = derive_type(ref_type, reftype_mode);
! 
! 				goto done;
! 			}
  		}
  
  		/*
*************** plpgsql_build_variable(const char *refna
*** 1903,1908 ****
--- 1985,1991 ----
  				row->dtype = PLPGSQL_DTYPE_ROW;
  				row->refname = pstrdup(refname);
  				row->lineno = lineno;
+ 				row->datatype = dtype;
  
  				plpgsql_adddatum((PLpgSQL_datum *) row);
  				if (add2namespace)
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
new file mode 100644
index 841a8d6..2a197a2
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
*************** static	void			check_raise_parameters(PLp
*** 248,253 ****
--- 248,254 ----
  %token <keyword>	K_ALIAS
  %token <keyword>	K_ALL
  %token <keyword>	K_ARRAY
+ %token <keyword>	K_ARRAYTYPE
  %token <keyword>	K_ASSERT
  %token <keyword>	K_BACKWARD
  %token <keyword>	K_BEGIN
*************** static	void			check_raise_parameters(PLp
*** 270,275 ****
--- 271,277 ----
  %token <keyword>	K_DETAIL
  %token <keyword>	K_DIAGNOSTICS
  %token <keyword>	K_DUMP
+ %token <keyword>	K_ELEMENTTYPE
  %token <keyword>	K_ELSE
  %token <keyword>	K_ELSIF
  %token <keyword>	K_END
*************** unreserved_keyword	:
*** 2390,2395 ****
--- 2392,2398 ----
  				K_ABSOLUTE
  				| K_ALIAS
  				| K_ARRAY
+ 				| K_ARRAYTYPE
  				| K_ASSERT
  				| K_BACKWARD
  				| K_CLOSE
*************** unreserved_keyword	:
*** 2408,2413 ****
--- 2411,2417 ----
  				| K_DETAIL
  				| K_DIAGNOSTICS
  				| K_DUMP
+ 				| K_ELEMENTTYPE
  				| K_ELSIF
  				| K_ERRCODE
  				| K_ERROR
*************** read_datatype(int tok)
*** 2690,2696 ****
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result;
  	int					parenlevel = 0;
  
  	/* Should only be called while parsing DECLARE sections */
--- 2694,2700 ----
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result = 0;
  	int					parenlevel = 0;
  
  	/* Should only be called while parsing DECLARE sections */
*************** read_datatype(int tok)
*** 2703,2710 ****
  	startlocation = yylloc;
  
  	/*
! 	 * If we have a simple or composite identifier, check for %TYPE
! 	 * and %ROWTYPE constructs.
  	 */
  	if (tok == T_WORD)
  	{
--- 2707,2714 ----
  	startlocation = yylloc;
  
  	/*
! 	 * If we have a simple or composite identifier, check for %TYPE,
! 	 * %ELEMENTTYPE, %ARRAYTYPE and %ROWTYPE constructs.
  	 */
  	if (tok == T_WORD)
  	{
*************** read_datatype(int tok)
*** 2716,2733 ****
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 			{
! 				result = plpgsql_parse_wordtype(dtname);
! 				if (result)
! 					return result;
! 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
--- 2720,2737 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
! 				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
! 				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_wordrowtype(dtname);
! 			if (result)
! 				return result;
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
*************** read_datatype(int tok)
*** 2740,2757 ****
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 			{
! 				result = plpgsql_parse_wordtype(dtname);
! 				if (result)
! 					return result;
! 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  	else if (tok == T_CWORD)
--- 2744,2761 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
! 				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
! 				result = plpgsql_parse_wordtype(dtname, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_wordrowtype(dtname);
! 			if (result)
! 				return result;
  		}
  	}
  	else if (tok == T_CWORD)
*************** read_datatype(int tok)
*** 2764,2781 ****
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 			{
! 				result = plpgsql_parse_cwordtype(dtnames);
! 				if (result)
! 					return result;
! 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  
--- 2768,2785 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
! 				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
! 				result = plpgsql_parse_cwordtype(dtnames, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 			if (result)
! 				return result;
  		}
  	}
  
diff --git a/src/pl/plpgsql/src/pl_scanner.c b/src/pl/plpgsql/src/pl_scanner.c
new file mode 100644
index 683fdab..6e34605
*** a/src/pl/plpgsql/src/pl_scanner.c
--- b/src/pl/plpgsql/src/pl_scanner.c
*************** static const ScanKeyword unreserved_keyw
*** 98,103 ****
--- 98,104 ----
  	PG_KEYWORD("absolute", K_ABSOLUTE, UNRESERVED_KEYWORD)
  	PG_KEYWORD("alias", K_ALIAS, UNRESERVED_KEYWORD)
  	PG_KEYWORD("array", K_ARRAY, UNRESERVED_KEYWORD)
+ 	PG_KEYWORD("arraytype", K_ARRAYTYPE, UNRESERVED_KEYWORD)
  	PG_KEYWORD("assert", K_ASSERT, UNRESERVED_KEYWORD)
  	PG_KEYWORD("backward", K_BACKWARD, UNRESERVED_KEYWORD)
  	PG_KEYWORD("close", K_CLOSE, UNRESERVED_KEYWORD)
*************** static const ScanKeyword unreserved_keyw
*** 116,121 ****
--- 117,123 ----
  	PG_KEYWORD("detail", K_DETAIL, UNRESERVED_KEYWORD)
  	PG_KEYWORD("diagnostics", K_DIAGNOSTICS, UNRESERVED_KEYWORD)
  	PG_KEYWORD("dump", K_DUMP, UNRESERVED_KEYWORD)
+ 	PG_KEYWORD("elementtype", K_ELEMENTTYPE, UNRESERVED_KEYWORD)
  	PG_KEYWORD("elseif", K_ELSIF, UNRESERVED_KEYWORD)
  	PG_KEYWORD("elsif", K_ELSIF, UNRESERVED_KEYWORD)
  	PG_KEYWORD("errcode", K_ERRCODE, UNRESERVED_KEYWORD)
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
new file mode 100644
index 696fb61..5b1a074
*** a/src/pl/plpgsql/src/plpgsql.h
--- b/src/pl/plpgsql/src/plpgsql.h
*************** enum
*** 84,89 ****
--- 84,100 ----
  };
  
  /* ----------
+  * Possible modes for type references
+  * ----------
+  */
+ enum
+ {
+ 	PLPGSQL_REFTYPE_TYPE,		/* use type of some variable */
+ 	PLPGSQL_REFTYPE_ELEMENT,	/* use a element type of referenced variable */
+ 	PLPGSQL_REFTYPE_ARRAY		/* use a array type of referenced variable */
+ };
+ 
+ /* ----------
   * Execution tree node types
   * ----------
   */
*************** typedef struct
*** 281,286 ****
--- 292,298 ----
  	char	   *refname;
  	int			lineno;
  
+ 	PLpgSQL_type *datatype;
  	TupleDesc	rowtupdesc;
  
  	/*
*************** extern bool plpgsql_parse_dblword(char *
*** 961,968 ****
  					  PLwdatum *wdatum, PLcword *cword);
  extern bool plpgsql_parse_tripword(char *word1, char *word2, char *word3,
  					   PLwdatum *wdatum, PLcword *cword);
! extern PLpgSQL_type *plpgsql_parse_wordtype(char *ident);
! extern PLpgSQL_type *plpgsql_parse_cwordtype(List *idents);
  extern PLpgSQL_type *plpgsql_parse_wordrowtype(char *ident);
  extern PLpgSQL_type *plpgsql_parse_cwordrowtype(List *idents);
  extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod,
--- 973,980 ----
  					  PLwdatum *wdatum, PLcword *cword);
  extern bool plpgsql_parse_tripword(char *word1, char *word2, char *word3,
  					   PLwdatum *wdatum, PLcword *cword);
! extern PLpgSQL_type *plpgsql_parse_wordtype(char *ident, int reftype_mode);
! extern PLpgSQL_type *plpgsql_parse_cwordtype(List *idents, int reftype_mode);
  extern PLpgSQL_type *plpgsql_parse_wordrowtype(char *ident);
  extern PLpgSQL_type *plpgsql_parse_cwordrowtype(List *idents);
  extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod,
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
new file mode 100644
index e30c579..b6e848b
*** a/src/test/regress/expected/plpgsql.out
--- b/src/test/regress/expected/plpgsql.out
*************** end;
*** 5573,5575 ****
--- 5573,5667 ----
  $$;
  ERROR:  unhandled assertion
  CONTEXT:  PL/pgSQL function inline_code_block line 3 at ASSERT
+ -- test referenced types
+ create type test_composite_type as (x int, y int);
+ create or replace function test_simple(src anyelement)
+ returns anyelement as $$
+ declare dest src%type;
+ begin
+   dest := src;
+   return dest;
+ end;
+ $$ language plpgsql;
+ select test_simple(10);
+  test_simple 
+ -------------
+           10
+ (1 row)
+ 
+ select test_simple('hoj'::text);
+  test_simple 
+ -------------
+  hoj
+ (1 row)
+ 
+ select test_simple((10,20)::test_composite_type);
+  test_simple 
+ -------------
+  (10,20)
+ (1 row)
+ 
+ create or replace function test_poly_element(x anyelement)
+ returns anyarray as $$
+ declare result x%arraytype;
+ begin
+   result := ARRAY[x];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ select test_poly_element(1);
+ NOTICE:  integer[] {1}
+  test_poly_element 
+ -------------------
+  {1}
+ (1 row)
+ 
+ select test_poly_element('hoj'::text);
+ NOTICE:  text[] {hoj}
+  test_poly_element 
+ -------------------
+  {hoj}
+ (1 row)
+ 
+ select test_poly_element((10,20)::test_composite_type);
+ NOTICE:  test_composite_type[] {"(10,20)"}
+  test_poly_element 
+ -------------------
+  {"(10,20)"}
+ (1 row)
+ 
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result x%elementtype;
+ begin
+   result := x[1];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ select test_poly_array(ARRAY[1]);
+ NOTICE:  integer 1
+  test_poly_array 
+ -----------------
+                1
+ (1 row)
+ 
+ select test_poly_array(ARRAY['hoj'::text]);
+ NOTICE:  text hoj
+  test_poly_array 
+ -----------------
+  hoj
+ (1 row)
+ 
+ select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+ NOTICE:  test_composite_type (10,20)
+  test_poly_array 
+ -----------------
+  (10,20)
+ (1 row)
+ 
+ drop function test_simple(anyelement);
+ drop type test_composite_type;
+ drop function test_poly_element(anyelement);
+ drop function test_poly_array(anyarray);
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
new file mode 100644
index 7ffef89..46bad10
*** a/src/test/regress/sql/plpgsql.sql
--- b/src/test/regress/sql/plpgsql.sql
*************** exception when others then
*** 4386,4388 ****
--- 4386,4437 ----
    null; -- do nothing
  end;
  $$;
+ 
+ -- test referenced types
+ create type test_composite_type as (x int, y int);
+ 
+ create or replace function test_simple(src anyelement)
+ returns anyelement as $$
+ declare dest src%type;
+ begin
+   dest := src;
+   return dest;
+ end;
+ $$ language plpgsql;
+ 
+ select test_simple(10);
+ select test_simple('hoj'::text);
+ select test_simple((10,20)::test_composite_type);
+ 
+ create or replace function test_poly_element(x anyelement)
+ returns anyarray as $$
+ declare result x%arraytype;
+ begin
+   result := ARRAY[x];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ select test_poly_element(1);
+ select test_poly_element('hoj'::text);
+ select test_poly_element((10,20)::test_composite_type);
+ 
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result x%elementtype;
+ begin
+   result := x[1];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ select test_poly_array(ARRAY[1]);
+ select test_poly_array(ARRAY['hoj'::text]);
+ select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+ 
+ drop function test_simple(anyelement);
+ drop type test_composite_type;
+ drop function test_poly_element(anyelement);
+ drop function test_poly_array(anyarray);

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
new file mode 100644
index 9786242..140c81f
*** a/doc/src/sgml/plpgsql.sgml
--- b/doc/src/sgml/plpgsql.sgml
*************** SELECT merge_fields(t.*) FROM table1 t W
*** 710,715 ****
--- 710,792 ----
     </para>
    </sect2>
  
+   <sect2 id="plpgsql-declaration-arraytype">
+    <title>Array Types</title>
+ 
+ <synopsis>
+ <replaceable>variable</replaceable>%ARRAYTYPE
+ </synopsis>
+ 
+    <para>
+     <literal>%ARRAYTYPE</literal> provides the array type from a variable or
+     table column. <literal>%ARRAYTYPE</literal> is particularly valuable in
+     polymorphic functions, since the data types needed for internal variables can
+     change from one call to the next.  Appropriate variables can be
+     created by applying <literal>%ARRAYTYPE</literal> to the function's
+     arguments or result placeholders:
+ <programlisting>
+ CREATE OR REPLACE FUNCTION array_init(v anyelement, size integer)
+ RETURNS anyarray AS $$
+ DECLARE
+     result v%ARRAYTYPE DEFAULT '{}';
+ BEGIN
+     -- prefer builtin function array_fill
+     FOR i IN 1 .. size
+     LOOP
+         result := result || v;
+     END LOOP;
+     RETURN result;
+ END;
+ $$ LANGUAGE plpgsql;
+ 
+ SELECT array_init(0::numeric, 10);
+ SELECT array_init(''::varchar, 10);
+ </programlisting>
+    </para>
+   </sect2>
+ 
+   <sect2 id="plpgsql-declaration-elementtype">
+    <title>Array Element Types</title>
+ 
+ <synopsis>
+ <replaceable>variable</replaceable>%ELEMENTTYPE
+ </synopsis>
+ 
+    <para>
+     <literal>%ELEMENTTYPE</literal> provides the element type of a given
+     array.  <literal>%ELEMENTTYPE</literal> is particularly valuable in polymorphic
+     functions, since the data types needed for internal variables can
+     change from one call to the next.  Appropriate variables can be
+     created by applying <literal>%ELEMENTTYPE</literal> to the function's
+     arguments or result placeholders:
+ <programlisting>
+ CREATE OR REPLACE FUNCTION bubble_sort(a anyarray)
+ RETURNS anyarray AS $$
+ DECLARE
+     aux a%ELEMENTTYPE;
+     repeat_again boolean DEFAULT true;
+ BEGIN
+     -- Don't use this code for large arrays!
+     -- use builtin sort
+     WHILE repeat_again
+     LOOP
+         repeat_again := false;
+         FOR i IN array_lower(a, 1) .. array_upper(a, 1)
+         LOOP
+             IF a[i] > a[i+1] THEN
+                 aux := a[i+1];
+                 a[i+1] := a[i]; a[i] := aux;
+                 repeat_again := true;
+             END IF;
+         END LOOP;
+     END LOOP;
+     RETURN a;
+ END;
+ $$ LANGUAGE plpgsql;
+ </programlisting>
+    </para>
+   </sect2>
+ 
    <sect2 id="plpgsql-declaration-collation">
     <title>Collation of <application>PL/pgSQL</application> Variables</title>
  
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
new file mode 100644
index ebe152d..98f74c3
*** a/src/pl/plpgsql/src/pl_comp.c
--- b/src/pl/plpgsql/src/pl_comp.c
*************** plpgsql_parse_tripword(char *word1, char
*** 1617,1632 ****
  	return false;
  }
  
  
  /* ----------
!  * plpgsql_parse_wordtype	The scanner found word%TYPE. word can be
!  *				a variable name or a basetype.
   *
   * Returns datatype struct, or NULL if no match found for word.
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_wordtype(char *ident)
  {
  	PLpgSQL_type *dtype;
  	PLpgSQL_nsitem *nse;
--- 1617,1683 ----
  	return false;
  }
  
+ /*
+  * Derive type from ny base type controlled by reftype.
+  *
+  * This routine allows to take array type from array variable. This behave
+  * is not consistent with enforce_generic_type_consistency, where same task
+  * fails on ERROR: 42704: could not find array type for data type xxxxxxx[].
+  */
+ static PLpgSQL_type *
+ derive_type(PLpgSQL_type *base_type, PLpgSQL_reftype reftype)
+ {
+ 	Oid typoid;
+ 
+ 	switch (reftype)
+ 	{
+ 		case PLPGSQL_REFTYPE_TYPE:
+ 			return base_type;
+ 
+ 		case PLPGSQL_REFTYPE_ELEMENT:
+ 		{
+ 			typoid = get_element_type(base_type->typoid);
+ 			if (!OidIsValid(typoid))
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_DATATYPE_MISMATCH),
+ 						 errmsg("referenced variable should be an array, not type %s",
+ 								format_type_be(base_type->typoid))));
+ 
+ 			return plpgsql_build_datatype(typoid, -1,
+ 							plpgsql_curr_compile->fn_input_collation);
+ 		}
+ 
+ 		case PLPGSQL_REFTYPE_ARRAY:
+ 		{
+ 			/* Return base_type, when it is a array already */
+ 			if (OidIsValid(get_element_type(base_type->typoid)))
+ 				return base_type;
+ 
+ 			typoid = get_array_type(base_type->typoid);
+ 			if (!OidIsValid(typoid))
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_DATATYPE_MISMATCH),
+ 						 errmsg("could not find array type for data type %s",
+ 								format_type_be(base_type->typoid))));
+ 
+ 			return plpgsql_build_datatype(typoid, -1,
+ 							plpgsql_curr_compile->fn_input_collation);
+ 		}
+ 
+ 		default:
+ 			return NULL;		/* keep compiler quiet */
+ 	}
+ }
  
  /* ----------
!  * plpgsql_parse_wordreftype	The scanner found word%TYPE or word%ARRAYTYPE
!  *				or word%ELEMENTTYPE. word can be a variable name or a basetype.
   *
   * Returns datatype struct, or NULL if no match found for word.
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_wordreftype(char *ident, PLpgSQL_reftype reftype)
  {
  	PLpgSQL_type *dtype;
  	PLpgSQL_nsitem *nse;
*************** plpgsql_parse_wordtype(char *ident)
*** 1644,1653 ****
  		switch (nse->itemtype)
  		{
  			case PLPGSQL_NSTYPE_VAR:
! 				return ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
  
! 				/* XXX perhaps allow REC/ROW here? */
  
  			default:
  				return NULL;
  		}
--- 1695,1715 ----
  		switch (nse->itemtype)
  		{
  			case PLPGSQL_NSTYPE_VAR:
! 			{
! 				dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				return derive_type(dtype, reftype);
! 			}
  
! 			case PLPGSQL_NSTYPE_ROW:
! 			{
! 				dtype = ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				return derive_type(dtype, reftype);
! 			}
  
+ 			/*
+ 			 * PLpgSQL doesn't support REC parameters, so we should not to
+ 			 * support REC here.
+ 			 */
  			default:
  				return NULL;
  		}
*************** plpgsql_parse_wordtype(char *ident)
*** 1685,1695 ****
  
  
  /* ----------
!  * plpgsql_parse_cwordtype		Same lookup for compositeword%TYPE
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_cwordtype(List *idents)
  {
  	PLpgSQL_type *dtype = NULL;
  	PLpgSQL_nsitem *nse;
--- 1747,1758 ----
  
  
  /* ----------
!  * plpgsql_parse_cwordreftype		Same lookup for compositeword%TYPE
!  *					compositeword%ARRAYTYPE or compositeword%ELEMENTTYPE
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_cwordreftype(List *idents, PLpgSQL_reftype reftype)
  {
  	PLpgSQL_type *dtype = NULL;
  	PLpgSQL_nsitem *nse;
*************** plpgsql_parse_cwordtype(List *idents)
*** 1718,1727 ****
  								NULL,
  								NULL);
  
! 		if (nse != NULL && nse->itemtype == PLPGSQL_NSTYPE_VAR)
  		{
! 			dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 			goto done;
  		}
  
  		/*
--- 1781,1804 ----
  								NULL,
  								NULL);
  
! 		if (nse != NULL)
  		{
! 			PLpgSQL_type *ref_type;
! 
! 			if (nse->itemtype == PLPGSQL_NSTYPE_VAR)
! 			{
! 				ref_type = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				dtype = derive_type(ref_type, reftype);
! 
! 				goto done;
! 			}
! 			else if (nse->itemtype == PLPGSQL_NSTYPE_ROW)
! 			{
! 				ref_type = ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				dtype = derive_type(ref_type, reftype);
! 
! 				goto done;
! 			}
  		}
  
  		/*
*************** plpgsql_build_variable(const char *refna
*** 1903,1908 ****
--- 1980,1986 ----
  				row->dtype = PLPGSQL_DTYPE_ROW;
  				row->refname = pstrdup(refname);
  				row->lineno = lineno;
+ 				row->datatype = dtype;
  
  				plpgsql_adddatum((PLpgSQL_datum *) row);
  				if (add2namespace)
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
new file mode 100644
index b14c22d..5048f54
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
*************** static	void			check_raise_parameters(PLp
*** 248,253 ****
--- 248,254 ----
  %token <keyword>	K_ALIAS
  %token <keyword>	K_ALL
  %token <keyword>	K_ARRAY
+ %token <keyword>	K_ARRAYTYPE
  %token <keyword>	K_ASSERT
  %token <keyword>	K_BACKWARD
  %token <keyword>	K_BEGIN
*************** static	void			check_raise_parameters(PLp
*** 270,275 ****
--- 271,277 ----
  %token <keyword>	K_DETAIL
  %token <keyword>	K_DIAGNOSTICS
  %token <keyword>	K_DUMP
+ %token <keyword>	K_ELEMENTTYPE
  %token <keyword>	K_ELSE
  %token <keyword>	K_ELSIF
  %token <keyword>	K_END
*************** unreserved_keyword	:
*** 2390,2395 ****
--- 2392,2398 ----
  				K_ABSOLUTE
  				| K_ALIAS
  				| K_ARRAY
+ 				| K_ARRAYTYPE
  				| K_ASSERT
  				| K_BACKWARD
  				| K_CLOSE
*************** unreserved_keyword	:
*** 2408,2413 ****
--- 2411,2417 ----
  				| K_DETAIL
  				| K_DIAGNOSTICS
  				| K_DUMP
+ 				| K_ELEMENTTYPE
  				| K_ELSIF
  				| K_ERRCODE
  				| K_ERROR
*************** read_datatype(int tok)
*** 2690,2696 ****
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result;
  	int					parenlevel = 0;
  
  	/* Should only be called while parsing DECLARE sections */
--- 2694,2700 ----
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result = 0;
  	int					parenlevel = 0;
  
  	/* Should only be called while parsing DECLARE sections */
*************** read_datatype(int tok)
*** 2703,2710 ****
  	startlocation = yylloc;
  
  	/*
! 	 * If we have a simple or composite identifier, check for %TYPE
! 	 * and %ROWTYPE constructs.
  	 */
  	if (tok == T_WORD)
  	{
--- 2707,2714 ----
  	startlocation = yylloc;
  
  	/*
! 	 * If we have a simple or composite identifier, check for %TYPE,
! 	 * %ELEMENTTYPE, %ARRAYTYPE and %ROWTYPE constructs.
  	 */
  	if (tok == T_WORD)
  	{
*************** read_datatype(int tok)
*** 2716,2733 ****
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 			{
! 				result = plpgsql_parse_wordtype(dtname);
! 				if (result)
! 					return result;
! 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
--- 2720,2737 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_wordrowtype(dtname);
! 			if (result)
! 				return result;
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
*************** read_datatype(int tok)
*** 2740,2757 ****
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 			{
! 				result = plpgsql_parse_wordtype(dtname);
! 				if (result)
! 					return result;
! 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  	else if (tok == T_CWORD)
--- 2744,2761 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_wordrowtype(dtname);
! 			if (result)
! 				return result;
  		}
  	}
  	else if (tok == T_CWORD)
*************** read_datatype(int tok)
*** 2764,2781 ****
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 			{
! 				result = plpgsql_parse_cwordtype(dtnames);
! 				if (result)
! 					return result;
! 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  
--- 2768,2785 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 				result = plpgsql_parse_cwordreftype(dtnames, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
! 				result = plpgsql_parse_cwordreftype(dtnames, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
! 				result = plpgsql_parse_cwordreftype(dtnames, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 			if (result)
! 				return result;
  		}
  	}
  
diff --git a/src/pl/plpgsql/src/pl_scanner.c b/src/pl/plpgsql/src/pl_scanner.c
new file mode 100644
index bb0f25b..9a5c54a
*** a/src/pl/plpgsql/src/pl_scanner.c
--- b/src/pl/plpgsql/src/pl_scanner.c
*************** static const ScanKeyword unreserved_keyw
*** 98,103 ****
--- 98,104 ----
  	PG_KEYWORD("absolute", K_ABSOLUTE, UNRESERVED_KEYWORD)
  	PG_KEYWORD("alias", K_ALIAS, UNRESERVED_KEYWORD)
  	PG_KEYWORD("array", K_ARRAY, UNRESERVED_KEYWORD)
+ 	PG_KEYWORD("arraytype", K_ARRAYTYPE, UNRESERVED_KEYWORD)
  	PG_KEYWORD("assert", K_ASSERT, UNRESERVED_KEYWORD)
  	PG_KEYWORD("backward", K_BACKWARD, UNRESERVED_KEYWORD)
  	PG_KEYWORD("close", K_CLOSE, UNRESERVED_KEYWORD)
*************** static const ScanKeyword unreserved_keyw
*** 116,121 ****
--- 117,123 ----
  	PG_KEYWORD("detail", K_DETAIL, UNRESERVED_KEYWORD)
  	PG_KEYWORD("diagnostics", K_DIAGNOSTICS, UNRESERVED_KEYWORD)
  	PG_KEYWORD("dump", K_DUMP, UNRESERVED_KEYWORD)
+ 	PG_KEYWORD("elementtype", K_ELEMENTTYPE, UNRESERVED_KEYWORD)
  	PG_KEYWORD("elseif", K_ELSIF, UNRESERVED_KEYWORD)
  	PG_KEYWORD("elsif", K_ELSIF, UNRESERVED_KEYWORD)
  	PG_KEYWORD("errcode", K_ERRCODE, UNRESERVED_KEYWORD)
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
new file mode 100644
index f4e9f62..41c3d74
*** a/src/pl/plpgsql/src/plpgsql.h
--- b/src/pl/plpgsql/src/plpgsql.h
*************** enum
*** 84,89 ****
--- 84,100 ----
  };
  
  /* ----------
+  * Possible modes for type references
+  * ----------
+  */
+ typedef enum
+ {
+ 	PLPGSQL_REFTYPE_TYPE,		/* use type of some variable */
+ 	PLPGSQL_REFTYPE_ELEMENT,	/* use a element type of referenced variable */
+ 	PLPGSQL_REFTYPE_ARRAY		/* use a array type of referenced variable */
+ } PLpgSQL_reftype;
+ 
+ /* ----------
   * Execution tree node types
   * ----------
   */
*************** typedef struct
*** 281,286 ****
--- 292,298 ----
  	char	   *refname;
  	int			lineno;
  
+ 	PLpgSQL_type *datatype;
  	TupleDesc	rowtupdesc;
  
  	/*
*************** extern bool plpgsql_parse_dblword(char *
*** 961,968 ****
  					  PLwdatum *wdatum, PLcword *cword);
  extern bool plpgsql_parse_tripword(char *word1, char *word2, char *word3,
  					   PLwdatum *wdatum, PLcword *cword);
! extern PLpgSQL_type *plpgsql_parse_wordtype(char *ident);
! extern PLpgSQL_type *plpgsql_parse_cwordtype(List *idents);
  extern PLpgSQL_type *plpgsql_parse_wordrowtype(char *ident);
  extern PLpgSQL_type *plpgsql_parse_cwordrowtype(List *idents);
  extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod,
--- 973,980 ----
  					  PLwdatum *wdatum, PLcword *cword);
  extern bool plpgsql_parse_tripword(char *word1, char *word2, char *word3,
  					   PLwdatum *wdatum, PLcword *cword);
! extern PLpgSQL_type *plpgsql_parse_wordreftype(char *ident, PLpgSQL_reftype reftype);
! extern PLpgSQL_type *plpgsql_parse_cwordreftype(List *idents, PLpgSQL_reftype reftype);
  extern PLpgSQL_type *plpgsql_parse_wordrowtype(char *ident);
  extern PLpgSQL_type *plpgsql_parse_cwordrowtype(List *idents);
  extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod,
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
new file mode 100644
index e30c579..1d6117e
*** a/src/test/regress/expected/plpgsql.out
--- b/src/test/regress/expected/plpgsql.out
*************** end;
*** 5573,5575 ****
--- 5573,5692 ----
  $$;
  ERROR:  unhandled assertion
  CONTEXT:  PL/pgSQL function inline_code_block line 3 at ASSERT
+ -- test referenced types
+ create type test_composite_type as (x int, y int);
+ create or replace function test_simple(src anyelement)
+ returns anyelement as $$
+ declare dest src%type;
+ begin
+   dest := src;
+   return dest;
+ end;
+ $$ language plpgsql;
+ select test_simple(10);
+  test_simple 
+ -------------
+           10
+ (1 row)
+ 
+ select test_simple('hoj'::text);
+  test_simple 
+ -------------
+  hoj
+ (1 row)
+ 
+ select test_simple((10,20)::test_composite_type);
+  test_simple 
+ -------------
+  (10,20)
+ (1 row)
+ 
+ create or replace function test_poly_element(x anyelement)
+ returns anyarray as $$
+ declare result x%arraytype;
+ begin
+   result := ARRAY[x];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ create or replace function test_array_init(v anyelement, size integer)
+ returns anyarray as $$
+ declare result v%arraytype default '{}';
+ begin
+   -- prefer builtin function array_fill
+   for i in 1 .. size
+   loop
+     result := result || v;
+   end loop;
+   return result;
+ end;
+ $$ language plpgsql;
+ select test_poly_element(1);
+ NOTICE:  integer[] {1}
+  test_poly_element 
+ -------------------
+  {1}
+ (1 row)
+ 
+ select test_poly_element('hoj'::text);
+ NOTICE:  text[] {hoj}
+  test_poly_element 
+ -------------------
+  {hoj}
+ (1 row)
+ 
+ select test_poly_element((10,20)::test_composite_type);
+ NOTICE:  test_composite_type[] {"(10,20)"}
+  test_poly_element 
+ -------------------
+  {"(10,20)"}
+ (1 row)
+ 
+ select test_array_init(1.0::numeric, 10);
+               test_array_init              
+ -------------------------------------------
+  {1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0}
+ (1 row)
+ 
+ select test_array_init(1::int, 10);
+     test_array_init    
+ -----------------------
+  {1,1,1,1,1,1,1,1,1,1}
+ (1 row)
+ 
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result x%elementtype;
+ begin
+   result := x[1];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ select test_poly_array(ARRAY[1]);
+ NOTICE:  integer 1
+  test_poly_array 
+ -----------------
+                1
+ (1 row)
+ 
+ select test_poly_array(ARRAY['hoj'::text]);
+ NOTICE:  text hoj
+  test_poly_array 
+ -----------------
+  hoj
+ (1 row)
+ 
+ select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+ NOTICE:  test_composite_type (10,20)
+  test_poly_array 
+ -----------------
+  (10,20)
+ (1 row)
+ 
+ drop function test_simple(anyelement);
+ drop type test_composite_type;
+ drop function test_poly_element(anyelement);
+ drop function test_array_init(anyelement, int);
+ drop function test_poly_array(anyarray);
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
new file mode 100644
index 7ffef89..85b8174
*** a/src/test/regress/sql/plpgsql.sql
--- b/src/test/regress/sql/plpgsql.sql
*************** exception when others then
*** 4386,4388 ****
--- 4386,4455 ----
    null; -- do nothing
  end;
  $$;
+ 
+ -- test referenced types
+ create type test_composite_type as (x int, y int);
+ 
+ create or replace function test_simple(src anyelement)
+ returns anyelement as $$
+ declare dest src%type;
+ begin
+   dest := src;
+   return dest;
+ end;
+ $$ language plpgsql;
+ 
+ select test_simple(10);
+ select test_simple('hoj'::text);
+ select test_simple((10,20)::test_composite_type);
+ 
+ create or replace function test_poly_element(x anyelement)
+ returns anyarray as $$
+ declare result x%arraytype;
+ begin
+   result := ARRAY[x];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ create or replace function test_array_init(v anyelement, size integer)
+ returns anyarray as $$
+ declare result v%arraytype default '{}';
+ begin
+   -- prefer builtin function array_fill
+   for i in 1 .. size
+   loop
+     result := result || v;
+   end loop;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ select test_poly_element(1);
+ select test_poly_element('hoj'::text);
+ select test_poly_element((10,20)::test_composite_type);
+ 
+ select test_array_init(1.0::numeric, 10);
+ select test_array_init(1::int, 10);
+ 
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result x%elementtype;
+ begin
+   result := x[1];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ 
+ select test_poly_array(ARRAY[1]);
+ select test_poly_array(ARRAY['hoj'::text]);
+ select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+ 
+ drop function test_simple(anyelement);
+ drop type test_composite_type;
+ drop function test_poly_element(anyelement);
+ drop function test_array_init(anyelement, int);
+ drop function test_poly_array(anyarray);

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
new file mode 100644
index 9786242..140c81f
*** a/doc/src/sgml/plpgsql.sgml
--- b/doc/src/sgml/plpgsql.sgml
*************** SELECT merge_fields(t.*) FROM table1 t W
*** 710,715 ****
--- 710,792 ----
     </para>
    </sect2>
  
+   <sect2 id="plpgsql-declaration-arraytype">
+    <title>Array Types</title>
+ 
+ <synopsis>
+ <replaceable>variable</replaceable>%ARRAYTYPE
+ </synopsis>
+ 
+    <para>
+     <literal>%ARRAYTYPE</literal> provides the array type from a variable or
+     table column. <literal>%ARRAYTYPE</literal> is particularly valuable in
+     polymorphic functions, since the data types needed for internal variables can
+     change from one call to the next.  Appropriate variables can be
+     created by applying <literal>%ARRAYTYPE</literal> to the function's
+     arguments or result placeholders:
+ <programlisting>
+ CREATE OR REPLACE FUNCTION array_init(v anyelement, size integer)
+ RETURNS anyarray AS $$
+ DECLARE
+     result v%ARRAYTYPE DEFAULT '{}';
+ BEGIN
+     -- prefer builtin function array_fill
+     FOR i IN 1 .. size
+     LOOP
+         result := result || v;
+     END LOOP;
+     RETURN result;
+ END;
+ $$ LANGUAGE plpgsql;
+ 
+ SELECT array_init(0::numeric, 10);
+ SELECT array_init(''::varchar, 10);
+ </programlisting>
+    </para>
+   </sect2>
+ 
+   <sect2 id="plpgsql-declaration-elementtype">
+    <title>Array Element Types</title>
+ 
+ <synopsis>
+ <replaceable>variable</replaceable>%ELEMENTTYPE
+ </synopsis>
+ 
+    <para>
+     <literal>%ELEMENTTYPE</literal> provides the element type of a given
+     array.  <literal>%ELEMENTTYPE</literal> is particularly valuable in polymorphic
+     functions, since the data types needed for internal variables can
+     change from one call to the next.  Appropriate variables can be
+     created by applying <literal>%ELEMENTTYPE</literal> to the function's
+     arguments or result placeholders:
+ <programlisting>
+ CREATE OR REPLACE FUNCTION bubble_sort(a anyarray)
+ RETURNS anyarray AS $$
+ DECLARE
+     aux a%ELEMENTTYPE;
+     repeat_again boolean DEFAULT true;
+ BEGIN
+     -- Don't use this code for large arrays!
+     -- use builtin sort
+     WHILE repeat_again
+     LOOP
+         repeat_again := false;
+         FOR i IN array_lower(a, 1) .. array_upper(a, 1)
+         LOOP
+             IF a[i] > a[i+1] THEN
+                 aux := a[i+1];
+                 a[i+1] := a[i]; a[i] := aux;
+                 repeat_again := true;
+             END IF;
+         END LOOP;
+     END LOOP;
+     RETURN a;
+ END;
+ $$ LANGUAGE plpgsql;
+ </programlisting>
+    </para>
+   </sect2>
+ 
    <sect2 id="plpgsql-declaration-collation">
     <title>Collation of <application>PL/pgSQL</application> Variables</title>
  
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
new file mode 100644
index ebe152d..07569f7
*** a/src/pl/plpgsql/src/pl_comp.c
--- b/src/pl/plpgsql/src/pl_comp.c
*************** plpgsql_parse_tripword(char *word1, char
*** 1617,1632 ****
  	return false;
  }
  
  
  /* ----------
!  * plpgsql_parse_wordtype	The scanner found word%TYPE. word can be
!  *				a variable name or a basetype.
   *
   * Returns datatype struct, or NULL if no match found for word.
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_wordtype(char *ident)
  {
  	PLpgSQL_type *dtype;
  	PLpgSQL_nsitem *nse;
--- 1617,1683 ----
  	return false;
  }
  
+ /*
+  * Derive type from any base type controlled by reftype.
+  *
+  * This routine allows to take array type from an array variable. This behave
+  * is not consistent with enforce_generic_type_consistency, where same task
+  * fails on ERROR: 42704: could not find array type for data type xxxxxxx[].
+  */
+ static PLpgSQL_type *
+ derive_type(PLpgSQL_type *base_type, PLpgSQL_reftype reftype)
+ {
+ 	Oid typoid;
+ 
+ 	switch (reftype)
+ 	{
+ 		case PLPGSQL_REFTYPE_TYPE:
+ 			return base_type;
+ 
+ 		case PLPGSQL_REFTYPE_ELEMENT:
+ 		{
+ 			typoid = get_element_type(base_type->typoid);
+ 			if (!OidIsValid(typoid))
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_DATATYPE_MISMATCH),
+ 						 errmsg("referenced variable should be an array, not type %s",
+ 								format_type_be(base_type->typoid))));
+ 
+ 			return plpgsql_build_datatype(typoid, -1,
+ 							plpgsql_curr_compile->fn_input_collation);
+ 		}
+ 
+ 		case PLPGSQL_REFTYPE_ARRAY:
+ 		{
+ 			/* Return base_type, when it is an array already */
+ 			if (OidIsValid(get_element_type(base_type->typoid)))
+ 				return base_type;
+ 
+ 			typoid = get_array_type(base_type->typoid);
+ 			if (!OidIsValid(typoid))
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_DATATYPE_MISMATCH),
+ 						 errmsg("could not find array type for data type %s",
+ 								format_type_be(base_type->typoid))));
+ 
+ 			return plpgsql_build_datatype(typoid, -1,
+ 							plpgsql_curr_compile->fn_input_collation);
+ 		}
+ 
+ 		default:
+ 			return NULL;		/* keep compiler quiet */
+ 	}
+ }
  
  /* ----------
!  * plpgsql_parse_wordreftype	The scanner found word%TYPE or word%ARRAYTYPE
!  *				or word%ELEMENTTYPE. word can be a variable name or a basetype.
   *
   * Returns datatype struct, or NULL if no match found for word.
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_wordreftype(char *ident, PLpgSQL_reftype reftype)
  {
  	PLpgSQL_type *dtype;
  	PLpgSQL_nsitem *nse;
*************** plpgsql_parse_wordtype(char *ident)
*** 1644,1653 ****
  		switch (nse->itemtype)
  		{
  			case PLPGSQL_NSTYPE_VAR:
! 				return ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
  
! 				/* XXX perhaps allow REC/ROW here? */
  
  			default:
  				return NULL;
  		}
--- 1695,1715 ----
  		switch (nse->itemtype)
  		{
  			case PLPGSQL_NSTYPE_VAR:
! 			{
! 				dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				return derive_type(dtype, reftype);
! 			}
  
! 			case PLPGSQL_NSTYPE_ROW:
! 			{
! 				dtype = ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				return derive_type(dtype, reftype);
! 			}
  
+ 			/*
+ 			 * XXX perhaps allow REC here? Currently PLpgSQL doesn't allow
+ 			 * REC parameters, so REC support is not required.
+ 			 */
  			default:
  				return NULL;
  		}
*************** plpgsql_parse_wordtype(char *ident)
*** 1685,1695 ****
  
  
  /* ----------
!  * plpgsql_parse_cwordtype		Same lookup for compositeword%TYPE
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_cwordtype(List *idents)
  {
  	PLpgSQL_type *dtype = NULL;
  	PLpgSQL_nsitem *nse;
--- 1747,1758 ----
  
  
  /* ----------
!  * plpgsql_parse_cwordreftype		Same lookup for compositeword%TYPE
!  *					compositeword%ARRAYTYPE or compositeword%ELEMENTTYPE
   * ----------
   */
  PLpgSQL_type *
! plpgsql_parse_cwordreftype(List *idents, PLpgSQL_reftype reftype)
  {
  	PLpgSQL_type *dtype = NULL;
  	PLpgSQL_nsitem *nse;
*************** plpgsql_parse_cwordtype(List *idents)
*** 1718,1727 ****
  								NULL,
  								NULL);
  
! 		if (nse != NULL && nse->itemtype == PLPGSQL_NSTYPE_VAR)
  		{
! 			dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 			goto done;
  		}
  
  		/*
--- 1781,1804 ----
  								NULL,
  								NULL);
  
! 		if (nse != NULL)
  		{
! 			PLpgSQL_type *ref_type;
! 
! 			if (nse->itemtype == PLPGSQL_NSTYPE_VAR)
! 			{
! 				ref_type = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				dtype = derive_type(ref_type, reftype);
! 
! 				goto done;
! 			}
! 			else if (nse->itemtype == PLPGSQL_NSTYPE_ROW)
! 			{
! 				ref_type = ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				dtype = derive_type(ref_type, reftype);
! 
! 				goto done;
! 			}
  		}
  
  		/*
*************** plpgsql_build_variable(const char *refna
*** 1903,1908 ****
--- 1980,1986 ----
  				row->dtype = PLPGSQL_DTYPE_ROW;
  				row->refname = pstrdup(refname);
  				row->lineno = lineno;
+ 				row->datatype = dtype;
  
  				plpgsql_adddatum((PLpgSQL_datum *) row);
  				if (add2namespace)
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
new file mode 100644
index b14c22d..5048f54
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
*************** static	void			check_raise_parameters(PLp
*** 248,253 ****
--- 248,254 ----
  %token <keyword>	K_ALIAS
  %token <keyword>	K_ALL
  %token <keyword>	K_ARRAY
+ %token <keyword>	K_ARRAYTYPE
  %token <keyword>	K_ASSERT
  %token <keyword>	K_BACKWARD
  %token <keyword>	K_BEGIN
*************** static	void			check_raise_parameters(PLp
*** 270,275 ****
--- 271,277 ----
  %token <keyword>	K_DETAIL
  %token <keyword>	K_DIAGNOSTICS
  %token <keyword>	K_DUMP
+ %token <keyword>	K_ELEMENTTYPE
  %token <keyword>	K_ELSE
  %token <keyword>	K_ELSIF
  %token <keyword>	K_END
*************** unreserved_keyword	:
*** 2390,2395 ****
--- 2392,2398 ----
  				K_ABSOLUTE
  				| K_ALIAS
  				| K_ARRAY
+ 				| K_ARRAYTYPE
  				| K_ASSERT
  				| K_BACKWARD
  				| K_CLOSE
*************** unreserved_keyword	:
*** 2408,2413 ****
--- 2411,2417 ----
  				| K_DETAIL
  				| K_DIAGNOSTICS
  				| K_DUMP
+ 				| K_ELEMENTTYPE
  				| K_ELSIF
  				| K_ERRCODE
  				| K_ERROR
*************** read_datatype(int tok)
*** 2690,2696 ****
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result;
  	int					parenlevel = 0;
  
  	/* Should only be called while parsing DECLARE sections */
--- 2694,2700 ----
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result = 0;
  	int					parenlevel = 0;
  
  	/* Should only be called while parsing DECLARE sections */
*************** read_datatype(int tok)
*** 2703,2710 ****
  	startlocation = yylloc;
  
  	/*
! 	 * If we have a simple or composite identifier, check for %TYPE
! 	 * and %ROWTYPE constructs.
  	 */
  	if (tok == T_WORD)
  	{
--- 2707,2714 ----
  	startlocation = yylloc;
  
  	/*
! 	 * If we have a simple or composite identifier, check for %TYPE,
! 	 * %ELEMENTTYPE, %ARRAYTYPE and %ROWTYPE constructs.
  	 */
  	if (tok == T_WORD)
  	{
*************** read_datatype(int tok)
*** 2716,2733 ****
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 			{
! 				result = plpgsql_parse_wordtype(dtname);
! 				if (result)
! 					return result;
! 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
--- 2720,2737 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_wordrowtype(dtname);
! 			if (result)
! 				return result;
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
*************** read_datatype(int tok)
*** 2740,2757 ****
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 			{
! 				result = plpgsql_parse_wordtype(dtname);
! 				if (result)
! 					return result;
! 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  	else if (tok == T_CWORD)
--- 2744,2761 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
! 				result = plpgsql_parse_wordreftype(dtname, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_wordrowtype(dtname);
! 			if (result)
! 				return result;
  		}
  	}
  	else if (tok == T_CWORD)
*************** read_datatype(int tok)
*** 2764,2781 ****
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 			{
! 				result = plpgsql_parse_cwordtype(dtnames);
! 				if (result)
! 					return result;
! 			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
- 			{
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 				if (result)
! 					return result;
! 			}
  		}
  	}
  
--- 2768,2785 ----
  			tok = yylex();
  			if (tok_is_keyword(tok, &yylval,
  							   K_TYPE, "type"))
! 				result = plpgsql_parse_cwordreftype(dtnames, PLPGSQL_REFTYPE_TYPE);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ELEMENTTYPE, "elementtype"))
! 				result = plpgsql_parse_cwordreftype(dtnames, PLPGSQL_REFTYPE_ELEMENT);
! 			else if (tok_is_keyword(tok, &yylval,
! 									K_ARRAYTYPE, "arraytype"))
! 				result = plpgsql_parse_cwordreftype(dtnames, PLPGSQL_REFTYPE_ARRAY);
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 			if (result)
! 				return result;
  		}
  	}
  
diff --git a/src/pl/plpgsql/src/pl_scanner.c b/src/pl/plpgsql/src/pl_scanner.c
new file mode 100644
index bb0f25b..9a5c54a
*** a/src/pl/plpgsql/src/pl_scanner.c
--- b/src/pl/plpgsql/src/pl_scanner.c
*************** static const ScanKeyword unreserved_keyw
*** 98,103 ****
--- 98,104 ----
  	PG_KEYWORD("absolute", K_ABSOLUTE, UNRESERVED_KEYWORD)
  	PG_KEYWORD("alias", K_ALIAS, UNRESERVED_KEYWORD)
  	PG_KEYWORD("array", K_ARRAY, UNRESERVED_KEYWORD)
+ 	PG_KEYWORD("arraytype", K_ARRAYTYPE, UNRESERVED_KEYWORD)
  	PG_KEYWORD("assert", K_ASSERT, UNRESERVED_KEYWORD)
  	PG_KEYWORD("backward", K_BACKWARD, UNRESERVED_KEYWORD)
  	PG_KEYWORD("close", K_CLOSE, UNRESERVED_KEYWORD)
*************** static const ScanKeyword unreserved_keyw
*** 116,121 ****
--- 117,123 ----
  	PG_KEYWORD("detail", K_DETAIL, UNRESERVED_KEYWORD)
  	PG_KEYWORD("diagnostics", K_DIAGNOSTICS, UNRESERVED_KEYWORD)
  	PG_KEYWORD("dump", K_DUMP, UNRESERVED_KEYWORD)
+ 	PG_KEYWORD("elementtype", K_ELEMENTTYPE, UNRESERVED_KEYWORD)
  	PG_KEYWORD("elseif", K_ELSIF, UNRESERVED_KEYWORD)
  	PG_KEYWORD("elsif", K_ELSIF, UNRESERVED_KEYWORD)
  	PG_KEYWORD("errcode", K_ERRCODE, UNRESERVED_KEYWORD)
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
new file mode 100644
index f4e9f62..41c3d74
*** a/src/pl/plpgsql/src/plpgsql.h
--- b/src/pl/plpgsql/src/plpgsql.h
*************** enum
*** 84,89 ****
--- 84,100 ----
  };
  
  /* ----------
+  * Possible modes for type references
+  * ----------
+  */
+ typedef enum
+ {
+ 	PLPGSQL_REFTYPE_TYPE,		/* use type of some variable */
+ 	PLPGSQL_REFTYPE_ELEMENT,	/* use a element type of referenced variable */
+ 	PLPGSQL_REFTYPE_ARRAY		/* use a array type of referenced variable */
+ } PLpgSQL_reftype;
+ 
+ /* ----------
   * Execution tree node types
   * ----------
   */
*************** typedef struct
*** 281,286 ****
--- 292,298 ----
  	char	   *refname;
  	int			lineno;
  
+ 	PLpgSQL_type *datatype;
  	TupleDesc	rowtupdesc;
  
  	/*
*************** extern bool plpgsql_parse_dblword(char *
*** 961,968 ****
  					  PLwdatum *wdatum, PLcword *cword);
  extern bool plpgsql_parse_tripword(char *word1, char *word2, char *word3,
  					   PLwdatum *wdatum, PLcword *cword);
! extern PLpgSQL_type *plpgsql_parse_wordtype(char *ident);
! extern PLpgSQL_type *plpgsql_parse_cwordtype(List *idents);
  extern PLpgSQL_type *plpgsql_parse_wordrowtype(char *ident);
  extern PLpgSQL_type *plpgsql_parse_cwordrowtype(List *idents);
  extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod,
--- 973,980 ----
  					  PLwdatum *wdatum, PLcword *cword);
  extern bool plpgsql_parse_tripword(char *word1, char *word2, char *word3,
  					   PLwdatum *wdatum, PLcword *cword);
! extern PLpgSQL_type *plpgsql_parse_wordreftype(char *ident, PLpgSQL_reftype reftype);
! extern PLpgSQL_type *plpgsql_parse_cwordreftype(List *idents, PLpgSQL_reftype reftype);
  extern PLpgSQL_type *plpgsql_parse_wordrowtype(char *ident);
  extern PLpgSQL_type *plpgsql_parse_cwordrowtype(List *idents);
  extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod,
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
new file mode 100644
index e30c579..1d6117e
*** a/src/test/regress/expected/plpgsql.out
--- b/src/test/regress/expected/plpgsql.out
*************** end;
*** 5573,5575 ****
--- 5573,5692 ----
  $$;
  ERROR:  unhandled assertion
  CONTEXT:  PL/pgSQL function inline_code_block line 3 at ASSERT
+ -- test referenced types
+ create type test_composite_type as (x int, y int);
+ create or replace function test_simple(src anyelement)
+ returns anyelement as $$
+ declare dest src%type;
+ begin
+   dest := src;
+   return dest;
+ end;
+ $$ language plpgsql;
+ select test_simple(10);
+  test_simple 
+ -------------
+           10
+ (1 row)
+ 
+ select test_simple('hoj'::text);
+  test_simple 
+ -------------
+  hoj
+ (1 row)
+ 
+ select test_simple((10,20)::test_composite_type);
+  test_simple 
+ -------------
+  (10,20)
+ (1 row)
+ 
+ create or replace function test_poly_element(x anyelement)
+ returns anyarray as $$
+ declare result x%arraytype;
+ begin
+   result := ARRAY[x];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ create or replace function test_array_init(v anyelement, size integer)
+ returns anyarray as $$
+ declare result v%arraytype default '{}';
+ begin
+   -- prefer builtin function array_fill
+   for i in 1 .. size
+   loop
+     result := result || v;
+   end loop;
+   return result;
+ end;
+ $$ language plpgsql;
+ select test_poly_element(1);
+ NOTICE:  integer[] {1}
+  test_poly_element 
+ -------------------
+  {1}
+ (1 row)
+ 
+ select test_poly_element('hoj'::text);
+ NOTICE:  text[] {hoj}
+  test_poly_element 
+ -------------------
+  {hoj}
+ (1 row)
+ 
+ select test_poly_element((10,20)::test_composite_type);
+ NOTICE:  test_composite_type[] {"(10,20)"}
+  test_poly_element 
+ -------------------
+  {"(10,20)"}
+ (1 row)
+ 
+ select test_array_init(1.0::numeric, 10);
+               test_array_init              
+ -------------------------------------------
+  {1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0}
+ (1 row)
+ 
+ select test_array_init(1::int, 10);
+     test_array_init    
+ -----------------------
+  {1,1,1,1,1,1,1,1,1,1}
+ (1 row)
+ 
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result x%elementtype;
+ begin
+   result := x[1];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ select test_poly_array(ARRAY[1]);
+ NOTICE:  integer 1
+  test_poly_array 
+ -----------------
+                1
+ (1 row)
+ 
+ select test_poly_array(ARRAY['hoj'::text]);
+ NOTICE:  text hoj
+  test_poly_array 
+ -----------------
+  hoj
+ (1 row)
+ 
+ select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+ NOTICE:  test_composite_type (10,20)
+  test_poly_array 
+ -----------------
+  (10,20)
+ (1 row)
+ 
+ drop function test_simple(anyelement);
+ drop type test_composite_type;
+ drop function test_poly_element(anyelement);
+ drop function test_array_init(anyelement, int);
+ drop function test_poly_array(anyarray);
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
new file mode 100644
index 7ffef89..85b8174
*** a/src/test/regress/sql/plpgsql.sql
--- b/src/test/regress/sql/plpgsql.sql
*************** exception when others then
*** 4386,4388 ****
--- 4386,4455 ----
    null; -- do nothing
  end;
  $$;
+ 
+ -- test referenced types
+ create type test_composite_type as (x int, y int);
+ 
+ create or replace function test_simple(src anyelement)
+ returns anyelement as $$
+ declare dest src%type;
+ begin
+   dest := src;
+   return dest;
+ end;
+ $$ language plpgsql;
+ 
+ select test_simple(10);
+ select test_simple('hoj'::text);
+ select test_simple((10,20)::test_composite_type);
+ 
+ create or replace function test_poly_element(x anyelement)
+ returns anyarray as $$
+ declare result x%arraytype;
+ begin
+   result := ARRAY[x];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ create or replace function test_array_init(v anyelement, size integer)
+ returns anyarray as $$
+ declare result v%arraytype default '{}';
+ begin
+   -- prefer builtin function array_fill
+   for i in 1 .. size
+   loop
+     result := result || v;
+   end loop;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ select test_poly_element(1);
+ select test_poly_element('hoj'::text);
+ select test_poly_element((10,20)::test_composite_type);
+ 
+ select test_array_init(1.0::numeric, 10);
+ select test_array_init(1::int, 10);
+ 
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result x%elementtype;
+ begin
+   result := x[1];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ 
+ select test_poly_array(ARRAY[1]);
+ select test_poly_array(ARRAY['hoj'::text]);
+ select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+ 
+ drop function test_simple(anyelement);
+ drop type test_composite_type;
+ drop function test_poly_element(anyelement);
+ drop function test_array_init(anyelement, int);
+ drop function test_poly_array(anyarray);

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
new file mode 100644
index 9786242..5587839
*** a/doc/src/sgml/plpgsql.sgml
--- b/doc/src/sgml/plpgsql.sgml
*************** url varchar;
*** 322,334 ****
  myrow tablename%ROWTYPE;
  myfield tablename.columnname%TYPE;
  arow RECORD;
  </programlisting>
      </para>
  
      <para>
       The general syntax of a variable declaration is:
  <synopsis>
! <replaceable>name</replaceable> <optional> CONSTANT </optional> <replaceable>type</replaceable> <optional> COLLATE <replaceable>collation_name</replaceable> </optional> <optional> NOT NULL </optional> <optional> { DEFAULT | := | = } <replaceable>expression</replaceable> </optional>;
  </synopsis>
        The <literal>DEFAULT</> clause, if given, specifies the initial value assigned
        to the variable when the block is entered.  If the <literal>DEFAULT</> clause
--- 322,336 ----
  myrow tablename%ROWTYPE;
  myfield tablename.columnname%TYPE;
  arow RECORD;
+ myarray tablename.columnname%TYPE[];
+ myelement ELEMENT OF arrayparam%TYPE;
  </programlisting>
      </para>
  
      <para>
       The general syntax of a variable declaration is:
  <synopsis>
! <replaceable>name</replaceable> <optional> CONSTANT </optional> <optional> ELEMENT OF </optional> <replaceable>type</replaceable> <optional> COLLATE <replaceable>collation_name</replaceable> </optional> <optional> NOT NULL </optional> <optional> { DEFAULT | := | = } <replaceable>expression</replaceable> </optional>;
  </synopsis>
        The <literal>DEFAULT</> clause, if given, specifies the initial value assigned
        to the variable when the block is entered.  If the <literal>DEFAULT</> clause
*************** arow RECORD;
*** 337,342 ****
--- 339,347 ----
        The <literal>CONSTANT</> option prevents the variable from being
        assigned to after initialization, so that its value will remain constant
        for the duration of the block.
+       The <literal>ELEMENT OF</> ensure using the element type of a given array type.
+       This construct is valuable in polymorphic functions, since the data types needed
+       for internal variables can change from one call to the next call.
        The <literal>COLLATE</> option specifies a collation to use for the
        variable (see <xref linkend="plpgsql-declaration-collation">).
        If <literal>NOT NULL</>
*************** user_id users.user_id%TYPE;
*** 611,616 ****
--- 616,666 ----
      change from one call to the next.  Appropriate variables can be
      created by applying <literal>%TYPE</literal> to the function's
      arguments or result placeholders.
+ <programlisting>
+ CREATE OR REPLACE FUNCTION array_init(v anyelement, size integer)
+ RETURNS anyarray AS $$
+ DECLARE
+     result v%TYPE[] DEFAULT '{}';
+ BEGIN
+     -- prefer builtin function array_fill
+     FOR i IN 1 .. size
+     LOOP
+         result := result || v;
+     END LOOP;
+     RETURN result;
+ END;
+ $$ LANGUAGE plpgsql;
+ 
+ SELECT array_init(0::numeric, 10);
+ SELECT array_init(''::varchar, 10);
+ 
+ 
+ CREATE OR REPLACE FUNCTION bubble_sort(a anyarray)
+ RETURNS anyarray AS $$
+ DECLARE
+     aux ELEMENT OF a%TYPE;
+     repeat_again boolean DEFAULT true;
+ BEGIN
+     -- Don't use this code for large arrays!
+     -- use builtin sort
+     WHILE repeat_again
+     LOOP
+         repeat_again := false;
+         FOR i IN array_lower(a, 1) .. array_upper(a, 1)
+         LOOP
+             IF a[i] > a[i+1] THEN
+                 aux := a[i+1];
+                 a[i+1] := a[i]; a[i] := aux;
+                 repeat_again := true;
+             END IF;
+         END LOOP;
+     END LOOP;
+     RETURN a;
+ END;
+ $$ LANGUAGE plpgsql;
+ 
+ SELECT bubble_sort(ARRAY[3,2,4,6,1]);
+ </programlisting>
     </para>
  
    </sect2>
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
new file mode 100644
index 2aeab96..b77117e
*** a/src/pl/plpgsql/src/pl_comp.c
--- b/src/pl/plpgsql/src/pl_comp.c
*************** plpgsql_parse_wordtype(char *ident)
*** 1646,1653 ****
  			case PLPGSQL_NSTYPE_VAR:
  				return ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
  
! 				/* XXX perhaps allow REC/ROW here? */
  
  			default:
  				return NULL;
  		}
--- 1646,1660 ----
  			case PLPGSQL_NSTYPE_VAR:
  				return ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
  
! 			case PLPGSQL_NSTYPE_ROW:
! 			{
! 				return ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
! 			}
  
+ 			/*
+ 			 * XXX perhaps allow REC here? Currently PLpgSQL doesn't allow
+ 			 * REC parameters, so REC support is not required.
+ 			 */
  			default:
  				return NULL;
  		}
*************** plpgsql_parse_cwordtype(List *idents)
*** 1718,1727 ****
  								NULL,
  								NULL);
  
! 		if (nse != NULL && nse->itemtype == PLPGSQL_NSTYPE_VAR)
  		{
! 			dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 			goto done;
  		}
  
  		/*
--- 1725,1742 ----
  								NULL,
  								NULL);
  
! 		if (nse != NULL)
  		{
! 			if (nse->itemtype == PLPGSQL_NSTYPE_VAR)
! 			{
! 				dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				goto done;
! 			}
! 			else if (nse->itemtype == PLPGSQL_NSTYPE_ROW)
! 			{
! 				dtype = ((PLpgSQL_row *) (plpgsql_Datums[nse->itemno]))->datatype;
! 				goto done;
! 			}
  		}
  
  		/*
*************** plpgsql_parse_cwordrowtype(List *idents)
*** 1852,1857 ****
--- 1867,1925 ----
  }
  
  /*
+  * This routine is used for generating element or array type from base type.
+  * The options to_element_type and to_array_type can be used together, when
+  * we would to ensure valid result. The array array type is original type, so
+  * this direction is safe. The element of scalar type is not allowed, but if
+  * we do "to array" transformation first, then this direction should be safe
+  * too. This design is tolerant, because we should to support a design of
+  * polymorphic parameters, where a array value can be passed as anyelement
+  * or anyarray parameter.
+  */
+ PLpgSQL_type *
+ plpgsql_derive_type(PLpgSQL_type *base_type,
+ 						bool to_element_type, bool to_array_type)
+ {
+ 	Oid		typid = base_type->typoid;
+ 
+ 	if (to_array_type)
+ 	{
+ 		/* do nothing if base_type is a array already */
+ 		if (!OidIsValid(get_element_type(typid)))
+ 		{
+ 			Oid array_typid = get_array_type(typid);
+ 
+ 			if (!OidIsValid(array_typid))
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_DATATYPE_MISMATCH),
+ 						 errmsg("could not find array type for data type %s",
+ 								format_type_be(typid))));
+ 			typid = array_typid;
+ 		}
+ 	}
+ 
+ 	if (to_element_type)
+ 	{
+ 		Oid element_typid = get_element_type(typid);
+ 
+ 		if (!OidIsValid(element_typid))
+ 			ereport(ERROR,
+ 					(errcode(ERRCODE_DATATYPE_MISMATCH),
+ 					 errmsg("referenced variable should be an array, not type %s",
+ 							format_type_be(typid))));
+ 			typid = element_typid;
+ 	}
+ 
+ 	/* when type is changed, construct new datatype */
+ 	if (typid != base_type->typoid)
+ 		return plpgsql_build_datatype(typid, -1,
+ 						plpgsql_curr_compile->fn_input_collation);
+ 
+ 	/* return original base_type, when any change is not required */
+ 	return base_type;
+ }
+ 
+ /*
   * plpgsql_build_variable - build a datum-array entry of a given
   * datatype
   *
*************** plpgsql_build_variable(const char *refna
*** 1903,1908 ****
--- 1971,1977 ----
  				row->dtype = PLPGSQL_DTYPE_ROW;
  				row->refname = pstrdup(refname);
  				row->lineno = lineno;
+ 				row->datatype = dtype;
  
  				plpgsql_adddatum((PLpgSQL_datum *) row);
  				if (add2namespace)
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
new file mode 100644
index df09575..5a05fed
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
*************** static	void			check_raise_parameters(PLp
*** 270,275 ****
--- 270,276 ----
  %token <keyword>	K_DETAIL
  %token <keyword>	K_DIAGNOSTICS
  %token <keyword>	K_DUMP
+ %token <keyword>	K_ELEMENT
  %token <keyword>	K_ELSE
  %token <keyword>	K_ELSIF
  %token <keyword>	K_END
*************** static	void			check_raise_parameters(PLp
*** 303,308 ****
--- 304,310 ----
  %token <keyword>	K_NOT
  %token <keyword>	K_NOTICE
  %token <keyword>	K_NULL
+ %token <keyword>	K_OF
  %token <keyword>	K_OPEN
  %token <keyword>	K_OPTION
  %token <keyword>	K_OR
*************** unreserved_keyword	:
*** 2408,2413 ****
--- 2410,2416 ----
  				| K_DETAIL
  				| K_DIAGNOSTICS
  				| K_DUMP
+ 				| K_ELEMENT
  				| K_ELSIF
  				| K_ERRCODE
  				| K_ERROR
*************** unreserved_keyword	:
*** 2429,2434 ****
--- 2432,2438 ----
  				| K_NEXT
  				| K_NO
  				| K_NOTICE
+ 				| K_OF
  				| K_OPEN
  				| K_OPTION
  				| K_PERFORM
*************** read_sql_construct(int until,
*** 2684,2697 ****
  	return expr;
  }
  
  static PLpgSQL_type *
  read_datatype(int tok)
  {
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result;
  	int					parenlevel = 0;
  
  	/* Should only be called while parsing DECLARE sections */
  	Assert(plpgsql_IdentifierLookup == IDENTIFIER_LOOKUP_DECLARE);
--- 2688,2745 ----
  	return expr;
  }
  
+ /*
+  * Returns true when following two tokens after %TYPE/%ROWTYPE are []
+  */
+ static bool
+ array_type_is_required(void)
+ {
+ 	int tok = yylex();
+ 
+ 	if (tok == '[')
+ 	{
+ 		tok = yylex();
+ 		if (tok != ']')
+ 			yyerror("syntax error, expected \"]\"");
+ 
+ 		return true;
+ 	}
+ 	else
+ 		plpgsql_push_back_token(tok);
+ 
+ 	return false;
+ }
+ 
+ /*
+  * Returns true when type is introducted by ELEMENT OF tokens
+  */
+ static bool
+ element_type_is_required(int tok)
+ {
+ 	if (tok_is_keyword(tok, &yylval,
+ 					   K_ELEMENT, "element"))
+ 	{
+ 		tok = yylex();
+ 		if (!tok_is_keyword(tok, &yylval, K_OF, "of"))
+ 			yyerror("syntax error, expected \"OF\"");
+ 
+ 		tok = yylex();
+ 		return true;
+ 	}
+ 
+ 	return false;
+ }
+ 
  static PLpgSQL_type *
  read_datatype(int tok)
  {
  	StringInfoData		ds;
  	char			   *type_name;
  	int					startlocation;
! 	PLpgSQL_type		*result = NULL;
  	int					parenlevel = 0;
+ 	bool				to_element_type = false;
+ 	bool				to_array_type = false;
  
  	/* Should only be called while parsing DECLARE sections */
  	Assert(plpgsql_IdentifierLookup == IDENTIFIER_LOOKUP_DECLARE);
*************** read_datatype(int tok)
*** 2700,2705 ****
--- 2748,2758 ----
  	if (tok == YYEMPTY)
  		tok = yylex();
  
+ 	/*
+ 	 * The request of element type can be first.
+ 	 */
+ 	to_element_type = element_type_is_required(tok);
+ 
  	startlocation = yylloc;
  
  	/*
*************** read_datatype(int tok)
*** 2718,2739 ****
  							   K_TYPE, "type"))
  			{
  				result = plpgsql_parse_wordtype(dtname);
- 				if (result)
- 					return result;
  			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
  			}
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
  	{
  		char   *dtname = pstrdup(yylval.keyword);
- 
  		tok = yylex();
  		if (tok == '%')
  		{
--- 2771,2794 ----
  							   K_TYPE, "type"))
  			{
  				result = plpgsql_parse_wordtype(dtname);
  			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 			}
! 
! 			if (result != NULL)
! 			{
! 				to_array_type = array_type_is_required();
! 				return plpgsql_derive_type(result,
! 											  to_element_type, to_array_type);
  			}
  		}
  	}
  	else if (plpgsql_token_is_unreserved_keyword(tok))
  	{
  		char   *dtname = pstrdup(yylval.keyword);
  		tok = yylex();
  		if (tok == '%')
  		{
*************** read_datatype(int tok)
*** 2742,2763 ****
  							   K_TYPE, "type"))
  			{
  				result = plpgsql_parse_wordtype(dtname);
- 				if (result)
- 					return result;
  			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 				if (result)
! 					return result;
  			}
  		}
  	}
  	else if (tok == T_CWORD)
  	{
  		List   *dtnames = yylval.cword.idents;
- 
  		tok = yylex();
  		if (tok == '%')
  		{
--- 2797,2820 ----
  							   K_TYPE, "type"))
  			{
  				result = plpgsql_parse_wordtype(dtname);
  			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  			{
  				result = plpgsql_parse_wordrowtype(dtname);
! 			}
! 
! 			if (result != NULL)
! 			{
! 				to_array_type = array_type_is_required();
! 				return plpgsql_derive_type(result,
! 											  to_element_type, to_array_type);
  			}
  		}
  	}
  	else if (tok == T_CWORD)
  	{
  		List   *dtnames = yylval.cword.idents;
  		tok = yylex();
  		if (tok == '%')
  		{
*************** read_datatype(int tok)
*** 2766,2780 ****
  							   K_TYPE, "type"))
  			{
  				result = plpgsql_parse_cwordtype(dtnames);
- 				if (result)
- 					return result;
  			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  			{
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 				if (result)
! 					return result;
  			}
  		}
  	}
--- 2823,2840 ----
  							   K_TYPE, "type"))
  			{
  				result = plpgsql_parse_cwordtype(dtnames);
  			}
  			else if (tok_is_keyword(tok, &yylval,
  									K_ROWTYPE, "rowtype"))
  			{
  				result = plpgsql_parse_cwordrowtype(dtnames);
! 			}
! 
! 			if (result != NULL)
! 			{
! 				to_array_type = array_type_is_required();
! 				return plpgsql_derive_type(result,
! 											  to_element_type, to_array_type);
  			}
  		}
  	}
*************** read_datatype(int tok)
*** 2817,2823 ****
  
  	plpgsql_push_back_token(tok);
  
! 	return result;
  }
  
  static PLpgSQL_stmt *
--- 2877,2884 ----
  
  	plpgsql_push_back_token(tok);
  
! 	return plpgsql_derive_type(result,
! 								    to_element_type, to_array_type);
  }
  
  static PLpgSQL_stmt *
diff --git a/src/pl/plpgsql/src/pl_scanner.c b/src/pl/plpgsql/src/pl_scanner.c
new file mode 100644
index bb0f25b..82959a9
*** a/src/pl/plpgsql/src/pl_scanner.c
--- b/src/pl/plpgsql/src/pl_scanner.c
*************** static const ScanKeyword unreserved_keyw
*** 116,121 ****
--- 116,122 ----
  	PG_KEYWORD("detail", K_DETAIL, UNRESERVED_KEYWORD)
  	PG_KEYWORD("diagnostics", K_DIAGNOSTICS, UNRESERVED_KEYWORD)
  	PG_KEYWORD("dump", K_DUMP, UNRESERVED_KEYWORD)
+ 	PG_KEYWORD("element", K_ELEMENT, UNRESERVED_KEYWORD)
  	PG_KEYWORD("elseif", K_ELSIF, UNRESERVED_KEYWORD)
  	PG_KEYWORD("elsif", K_ELSIF, UNRESERVED_KEYWORD)
  	PG_KEYWORD("errcode", K_ERRCODE, UNRESERVED_KEYWORD)
*************** static const ScanKeyword unreserved_keyw
*** 138,143 ****
--- 139,145 ----
  	PG_KEYWORD("next", K_NEXT, UNRESERVED_KEYWORD)
  	PG_KEYWORD("no", K_NO, UNRESERVED_KEYWORD)
  	PG_KEYWORD("notice", K_NOTICE, UNRESERVED_KEYWORD)
+ 	PG_KEYWORD("of", K_OF, UNRESERVED_KEYWORD)
  	PG_KEYWORD("open", K_OPEN, UNRESERVED_KEYWORD)
  	PG_KEYWORD("option", K_OPTION, UNRESERVED_KEYWORD)
  	PG_KEYWORD("perform", K_PERFORM, UNRESERVED_KEYWORD)
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
new file mode 100644
index a1e900d..f3c563c
*** a/src/pl/plpgsql/src/plpgsql.h
--- b/src/pl/plpgsql/src/plpgsql.h
*************** typedef struct
*** 281,286 ****
--- 281,287 ----
  	char	   *refname;
  	int			lineno;
  
+ 	PLpgSQL_type *datatype;
  	TupleDesc	rowtupdesc;
  
  	/*
*************** extern PLpgSQL_type *plpgsql_parse_wordt
*** 965,970 ****
--- 966,973 ----
  extern PLpgSQL_type *plpgsql_parse_cwordtype(List *idents);
  extern PLpgSQL_type *plpgsql_parse_wordrowtype(char *ident);
  extern PLpgSQL_type *plpgsql_parse_cwordrowtype(List *idents);
+ extern PLpgSQL_type *plpgsql_derive_type(PLpgSQL_type *base_type,
+ 						bool to_element_type, bool to_array_type);
  extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod,
  					   Oid collation);
  extern PLpgSQL_variable *plpgsql_build_variable(const char *refname, int lineno,
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
new file mode 100644
index e30c579..2cb207e
*** a/src/test/regress/expected/plpgsql.out
--- b/src/test/regress/expected/plpgsql.out
*************** end;
*** 5573,5575 ****
--- 5573,5729 ----
  $$;
  ERROR:  unhandled assertion
  CONTEXT:  PL/pgSQL function inline_code_block line 3 at ASSERT
+ -- test referenced types
+ create type test_composite_type as (x int, y int);
+ create domain array_domain as int[];
+ create domain int_domain as int;
+ create or replace function test_simple(src anyelement)
+ returns anyelement as $$
+ declare dest src%type;
+ begin
+   dest := src;
+   return dest;
+ end;
+ $$ language plpgsql;
+ select test_simple(10);
+  test_simple 
+ -------------
+           10
+ (1 row)
+ 
+ select test_simple('hoj'::text);
+  test_simple 
+ -------------
+  hoj
+ (1 row)
+ 
+ select test_simple((10,20)::test_composite_type);
+  test_simple 
+ -------------
+  (10,20)
+ (1 row)
+ 
+ create or replace function test_poly_element(x anyelement)
+ returns anyarray as $$
+ declare result x%type[];
+ begin
+   result := ARRAY[x];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ create or replace function test_array_init(v anyelement, size integer)
+ returns anyarray as $$
+ declare result v%type[] default '{}';
+ begin
+   -- prefer builtin function array_fill
+   for i in 1 .. size
+   loop
+     result := result || v;
+   end loop;
+   return result;
+ end;
+ $$ language plpgsql;
+ select test_poly_element(1);
+ NOTICE:  integer[] {1}
+  test_poly_element 
+ -------------------
+  {1}
+ (1 row)
+ 
+ select test_poly_element('hoj'::text);
+ NOTICE:  text[] {hoj}
+  test_poly_element 
+ -------------------
+  {hoj}
+ (1 row)
+ 
+ select test_poly_element((10,20)::test_composite_type);
+ NOTICE:  test_composite_type[] {"(10,20)"}
+  test_poly_element 
+ -------------------
+  {"(10,20)"}
+ (1 row)
+ 
+ select test_array_init(1.0::numeric, 10);
+               test_array_init              
+ -------------------------------------------
+  {1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0}
+ (1 row)
+ 
+ select test_array_init(1::int, 10);
+     test_array_init    
+ -----------------------
+  {1,1,1,1,1,1,1,1,1,1}
+ (1 row)
+ 
+ -- should fail, there are no array type for scalar domain
+ select test_poly_element(1::int_domain);
+ ERROR:  could not find array type for data type int_domain
+ select test_array_init(1::int_domain, 10);
+ ERROR:  could not find array type for data type int_domain
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result element of x%type;
+ begin
+   result := x[1];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ select test_poly_array(ARRAY[1]);
+ NOTICE:  integer 1
+  test_poly_array 
+ -----------------
+                1
+ (1 row)
+ 
+ select test_poly_array(ARRAY['hoj'::text]);
+ NOTICE:  text hoj
+  test_poly_array 
+ -----------------
+  hoj
+ (1 row)
+ 
+ select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+ NOTICE:  test_composite_type (10,20)
+  test_poly_array 
+ -----------------
+  (10,20)
+ (1 row)
+ 
+ select test_poly_array(ARRAY[1,2,3,4]::array_domain);
+ NOTICE:  integer 1
+  test_poly_array 
+ -----------------
+                1
+ (1 row)
+ 
+ drop function test_simple(anyelement);
+ drop type test_composite_type;
+ drop domain array_domain;
+ drop domain int_domain;
+ drop function test_poly_element(anyelement);
+ drop function test_array_init(anyelement, int);
+ drop function test_poly_array(anyarray);
+ -- should fail, syntax errors
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result element x%type;
+ begin
+   return result;
+ end;
+ $$ language plpgsql;
+ ERROR:  syntax error, expected "OF" at or near "x"
+ LINE 3: declare result element x%type;
+                                ^
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result x%type[;
+ begin
+   return result;
+ end;
+ $$ language plpgsql;
+ ERROR:  syntax error, expected "]" at or near ";"
+ LINE 3: declare result x%type[;
+                               ^
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
new file mode 100644
index 7ffef89..0e16260
*** a/src/test/regress/sql/plpgsql.sql
--- b/src/test/regress/sql/plpgsql.sql
*************** exception when others then
*** 4386,4388 ****
--- 4386,4482 ----
    null; -- do nothing
  end;
  $$;
+ 
+ 
+ -- test referenced types
+ create type test_composite_type as (x int, y int);
+ create domain array_domain as int[];
+ create domain int_domain as int;
+ 
+ create or replace function test_simple(src anyelement)
+ returns anyelement as $$
+ declare dest src%type;
+ begin
+   dest := src;
+   return dest;
+ end;
+ $$ language plpgsql;
+ 
+ select test_simple(10);
+ select test_simple('hoj'::text);
+ select test_simple((10,20)::test_composite_type);
+ 
+ create or replace function test_poly_element(x anyelement)
+ returns anyarray as $$
+ declare result x%type[];
+ begin
+   result := ARRAY[x];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ create or replace function test_array_init(v anyelement, size integer)
+ returns anyarray as $$
+ declare result v%type[] default '{}';
+ begin
+   -- prefer builtin function array_fill
+   for i in 1 .. size
+   loop
+     result := result || v;
+   end loop;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ select test_poly_element(1);
+ select test_poly_element('hoj'::text);
+ select test_poly_element((10,20)::test_composite_type);
+ 
+ select test_array_init(1.0::numeric, 10);
+ select test_array_init(1::int, 10);
+ 
+ -- should fail, there are no array type for scalar domain
+ select test_poly_element(1::int_domain);
+ select test_array_init(1::int_domain, 10);
+ 
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result element of x%type;
+ begin
+   result := x[1];
+   raise notice '% %', pg_typeof(result), result;
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ select test_poly_array(ARRAY[1]);
+ select test_poly_array(ARRAY['hoj'::text]);
+ select test_poly_array(ARRAY[(10,20)::test_composite_type]);
+ select test_poly_array(ARRAY[1,2,3,4]::array_domain);
+ 
+ drop function test_simple(anyelement);
+ drop type test_composite_type;
+ drop domain array_domain;
+ drop domain int_domain;
+ 
+ drop function test_poly_element(anyelement);
+ drop function test_array_init(anyelement, int);
+ drop function test_poly_array(anyarray);
+ 
+ -- should fail, syntax errors
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result element x%type;
+ begin
+   return result;
+ end;
+ $$ language plpgsql;
+ 
+ create or replace function test_poly_array(x anyarray)
+ returns anyelement as $$
+ declare result x%type[;
+ begin
+   return result;
+ end;
+ $$ language plpgsql;