moving parse error to errors.py, and renaming for consistency
adding unit tests for when the wrong numbers of arguments are given to built-ins
spelling fix
ensure lambda parameter list is a list, and only contains symbols
documenting type errors and function signatures of built-ins
grammar fix
removing completed todo
implementing a basic macro system
moving all the source code files to a subdirectory
alternative naming for quote
adding a todo regarding reusing list literals
fixing same? to correctly handle more types
add lexer support for keywords