Use Token class instead of storing token values as NSString.
Upgrade project settings.
Refactor in paradise (Kauai).
Refactor: Node now has a Token property.
Specific token types for '(' and ')'.
Remove 'func' TokenType.
Add NodeType.
Add 'paren' method on TokenType.
Remove Node.numArgs.
Update comment.
Determine NodeType, part 1.
Set NodeType on Node.
Fake function evaluation.