weiping He <laser@zhengmai.com.cn> writes:
> create or replace function test() returns integer as '
> begin
> -- raise NOTICE ''can't comment out!'';
                       ^
You have to double that quote mark, too.  The string-literal parser
doesn't pay any attention to what's inside the string; the fact that
this area of the string would be a comment according to plpgsql's
rules doesn't change what the parser is going to think is the end of
the string literal.
            regards, tom lane