Remove code for parsing transform expressions; they've been replaced by appropriate methods.
Clarify a comment.
Combine exprBeforeMethods with the part with the methods, call it basicExpr.
Add support for math and booleans.
Use pyparsing's pythonStyleComment, rather than implement it myself.
Give lots of pyparsing grammar elements names and resultNames.
Combine number with numberWithUnit (make unit optional).
Prefer literal to varName (e.g. 'true' is a literal) in mathExpr.
Fix exception in IfStmt.__repr__ by correctly using unicode strings.
Use repr() for some objects in IfStmt.__repr__()
Use MatchFirst instead of Or, is faster and Or isn't necessary.
Use Keyword instead of Literal for unit names.
Don't bother trying to parse a stmt if at a closing bracket or end of string.
Remove unnecessary parensExpr and an old comment.
Remove separate basicExpr, combine it with expr.
Add some names, use some previously defined resultNames.
Add a TODO comment.
Allow function calls to be used in math expressions.
Allow method calls in math expressions.
Enable pyparsing's packrat parsing, for a great speedup.