pLERO is a formal specification language for preserving knowledge of grammar engineers, complementing mARTINICA, the universal approach for automated refactoring of context-free grammars.

Experimental implementation of pLERO pattern application system: pLERO version 0.1 ¹⁾

To run pLERO you need Java Runtime Environment 7. To execute pattern application, use command line:

java -jar plero.jar <pattern-file> <grammar-file>

While pattern is defined in the pLERO language, grammar is specified in a simple grammar format based on Backus-Naur Form.