numbers format

in pg is function to_hex () , but there is no function to_dec,
but there could be auto conversion like in c/c++ and others lang.

select 0x64;
select 0312;

( and like in asm select 01010101b; :-)

and also :

select char(0x64);

or conversion :

select '0x64' :: int;

need to change parser ?