A3 Notes

• nonterminal variable needs Readable for use in inputs

  • solution: expn.VarRefExpn

• inputs -- should have been variablename, not variable

• IdentExpn, and SubsExpn, need a common ancesstor that implements Readable

• remove MultiDeclaration

  • MultiDeclarations -> VarDeclarations
  • Declaration was only dealing with "name and type", which didn't fit multiple variable declarations or procedures

• AST nodes are immutable: set permanently at construction time

• Add ForwardRoutine, ForwardRoutineDecl

• RoutinePrototype (procedure vs function, return type, parameter list of name & types)

• fix nonterminal 'Program' to be of type 'Program'