plpgsql, declare blocks, and '=' versus ':='

It seems that [ in 8.2.9 at least ], in a plpgsql declare block,
assignment to declared variable can use either the proper ':='
operator or the unexpected and undocumented '=' operator. See
following script. The magic handling of '=' ought to get documented at
least.

[ plpgsql-declarations.html makes no mention of '=' token handling in
either 8.3 or 8.2. docs ]

---
create or replace function test_1() returns int as
$$
declare
value int = 12; -- wow -- no colon!
begin
return value;
end;
$$ language plpgsql;

create or replace function test_2() returns int as
$$
declare
value int := 14; -- correct
begin
return value;
end;
$$ language plpgsql;

select test_1();
-- returns 12

select test_2();
-- returns 14

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James Robinson
Socialserve.com