Language::Expr::Interpreter::VarEnumer - Enumerate variables mentioned in Language::Expr expression
Store the list of variables seen during parsing.
Add variable to result if it is not already in there.
Currently $_ in map/grep variables and $a & $b in usort are counted.
Steven Haryanto <email@example.com>
This software is copyright (c) 2013 by Steven Haryanto.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.