As with many things in the Unix universe, the saying, "Nothing can parse Perl except perl" is case-sensitive. The saying means, "Nothing can parse the language of Perl except the executable called perl."

The Windows equivalent would be: "Nothing can parse Perl except PERL.EXE."

The saying is NOT trying to suggest that a Perl script can flawlessly parse Perl language snippets. That is a common misconception and misunderstanding. A parser written in Perl can do a lot, but any parser you're likely(*) to write in Perl will fail to parse all of the Perl language.

The wisdom in this koan is to realize that the Perl language is so crufty with special-cases and funky exceptions to its own grammars that it would be folly to try to parse any Perl script by writing a parser from scratch. Even the human brain can't always parse Perl in many cases. You'll get hung up on the many years of grammar evolution.

(*) Unless you're implementing Perl6, which is really just using Perl6 to plan Perl6.

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[ e d @ h a l l e y . c c ]

In reply to Re^4: Only perl parses perl hash notation? by halley
in thread Only perl parses perl hash notation? by Eyck

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