There was a short paper in Inforum 2010 analyzing the current state of parsers in Perl. See Parser Generation in Perl: an Overview and Available Tools by Hugo Areias et al.

They conclude:

Parser generators in Perl still lacks valuable mechanisms to make them challengeable when compared with other languages, like C. There is no valid support for attribute grammars and, according to the research made, there is only one module on CPAN that supports attribute grammars that, however, lacks of maintenance for several years now.

I have tried myself to improve yacc-like conflict resolution mechanism with a new mechanism called "Postoponed Conflict Resolution" (PPCR). You can see how it is used in several Eyapp examples, See the following files in the t/ directory of the Eyapp distribution:

1. dynamic.eyp
2. pascalnestedeyapp3
3. CplusplusNested2.eyp

The first shows how you can use PPCR to dynamically change the parsing and consequently the abstract syntax trees on the fly.

The second solves the problem of enumerated types versus range types that appears in Extended Pascal. It has been used in the Bison manual to illustrate the power of GLR.

The third one solves the well known C++ ambiguity between certain declarations and statements.

To compile them, install Parse::Eyapp and follow the perldoc instructions in the grammars.

I still believe it is important for the Perl community to cover some important parsing algorithms. There is no currently in CPAN an implementation of GLR, which is important not only when writing translators for DSLs but also in Natural Language Processing

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