This and other RFCs are available on the web at http://dev.perl.org/rfc/ =head1 TITLE hashes should interpolate in double-quoted strings =head1 VERSION Maintainer: Nathan Torkington <[EMAIL PROTECTED]> Date: 15 Sep 2000 Mailing List: [EMAIL PROTECTED] Number: 237 Version: 1 Status: Developing =head1 ABSTRACT "%hash" should expand to: join( $/, map { qq($_$"$hash{$_}) } keys %hash ) =head1 DESCRIPTION Hashes do not interpolate in double-quote context in perl5. They should, because (a) scalars and arrays do, (b) it is a useful thing. The problem has always been: how to separate the keys and values? I say use $" (the value that gets put between array elements in double-quote interpolation) between key and value, and $/ between each hash record. A thorn is that $/ is the B<input> record separator. It seems wrong to use it for output. But $\ is not set by default, and it seems unreasonable to have to set $\ (which affects the end of every print) just to interpolate hashes. I didn't relish making yet another special variable just for this, though. When global variables like $" and $/ go away, I imagine they'll be replaced with lexically-scoped variations. This will work then, too. The big problem is that % is heavily used in double-quoted strings with printf. I don't have a solution to this. In the end, this may be B<the> definitive reason why hashes do not interpolate. And that's fine by me. =head1 IMPLEMENTATION A simple change to the tokenizer. The perl526 translator could backslash every % in a double-quoted string. =head1 REFERENCES None.
