Parse::Eyapp (Extended yapp) is a collection of modules that extends Francois Desarmenien Parse::Yapp 1.05. Eyapp extends yacc/yapp syntax with functionalities like named attributes, EBNF-like expressions, modifiable default action, grammar reusability, data generation, automatic syntax tree building, semi-automatic abstract syntax tree building, translation schemes, tree regular expressions, tree transformations, scope analysis support, directed acyclic graphs and a few more.