TITLE

use syntax

VERSION

  Maintainer: Simon Cozens <simon@brecon.co.uk>
  Date: 28 Sep 2000
  Mailing List: perl6-language@perl.org
  Number: 329
  Version: 1
  Status: Developing

ABSTRACT

A pragma to modify the syntax of Perl 6 at run time. Oh yes.

DESCRIPTION

So, maybe the Perl 6 crack pipe finally got around to me, but it seems to me that if we've got a parser that we can modify and add hooks to in Perl space (see RFC 314) then we can alter Perl's syntax using pragmata.

Combining this with source filters means that we can arrange for the line

    use syntax "perl5";

to enable legacy Perl programs to run under Perl 6.

I briefly considered

    {
        use syntax "python";
    }

and nearly lost my lunch.

Seriously, though, I think if we have a flexible parser that we can modify in Perl space, interpreting legacy versions of Perl or inferior languages could quite definitely become possible.

IMPLEMENTATION

First, implement 314. Then construct grammars for what we want to parse, and ensure that the parser is flexible enough to allow them as alternate grammars.

REFERENCES