declare_functions_visitor.py 1.7 KB

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  1. import symbol_table as st
  2. import types_mv
  3. from visitor import Visitor
  4. # Declare the function but do not visit its body
  5. class DeclareFunctionsVisitor(Visitor):
  6. def __init__(self, symbol_table, inputfiles):
  7. Visitor.__init__(self, [])
  8. self.symbol_table = symbol_table
  9. self.inputfiles = inputfiles
  10. def compute_parameter_types(self, tree):
  11. parameter_types = []
  12. for parameter in tree.get_children('parameter'):
  13. type_specifier = parameter.get_tail()[2].get_text()
  14. parameter_types.append(types_mv.string_to_type(type_specifier))
  15. return parameter_types
  16. def compute_func_type(self, tree):
  17. self.visit(tree.get_tail()[0])
  18. func_type = self.get_type(tree.get_tail()[0])
  19. return func_type
  20. def visit_funcdecl(self, tree):
  21. func_name = tree.get_tail()[2].get_text()
  22. func_type = self.compute_func_type(tree)
  23. parameter_types = self.compute_parameter_types(tree)
  24. self.set_type(tree, func_type)
  25. #TODO should check type compatibility if declared multiple times
  26. try:
  27. s = st.Symbol(func_name, func_type, is_global=True, params=parameter_types)
  28. self.symbol_table.add(s)
  29. except Exception:
  30. if "COLON" in tree.get_tail() or "ASSIGN" in tree.get_tail():
  31. raise RuntimeError(
  32. "{}:{}:{}: error: redeclaration of '{}'".format(
  33. self.inputfiles[0], tree.startpos['line'],
  34. tree.startpos['column'], func_name))
  35. self.set_symbol(tree, s)
  36. def visit_func_type(self, tree):
  37. self.set_type(tree, types_mv.string_to_type(tree.get_text()))