def visit(self, node: ast.VariableNode, scope: Scope):
variable = scope.find_variable(node.lex)
if variable is None:
self.errors.append(err.VARIABLE_NOT_DEFINED %
(node.lex, self.current_method.name))
return ErrorType()
return variable.type
def visit(self, node: ast.AssignNode, scope: Scope):
variable_info = scope.find_variable(node.id)
if variable_info is None:
self.current_instance.set_attribute_instance(node.id, self.visit(node.expr, scope))
return self.current_instance.get_attribute_instance(node.id)
variable_info.instance = self.visit(node.expr, scope)
return variable_info.instance
def visit(self, node: ast.VariableNode, scope: Scope):
var_info = scope.find_variable(node.lex)
if var_info is not None:
if var_info.type.name == "AUTO_TYPE":
return self.variables[var_info]
else:
return AtomNode(var_info.type)
else:
return None
def visit(self, node: ast.AttrDeclarationNode, scope: Scope):
attr_type = self.context.get_type(node.type)
var_info = scope.find_variable(node.id)
if node.expr is not None:
self.visit(node.expr, scope.children[node.index])
if attr_type == self.context.get_type("AUTO_TYPE"):
if var_info.type == self.context.get_type("AUTO_TYPE"):
self.errors.append(err.INFERENCE_ERROR_ATTRIBUTE % node.id)
node.type = var_info.type.name
def visit(self, node: ast.VariableNode, scope: Scope):
variable = scope.find_variable(node.lex)
if variable is None:
if self.current_attribute is not None:
name = self.current_attribute.name
else:
name = self.current_method.name
self.errors.append(err.UNDEFINED_VARIABLE %
(node.line, node.column, node.lex, name))
return ErrorType()
return variable.type
def visit(self, node: ast.AssignNode, scope: Scope):
var_info = scope.find_variable(node.id)
expr_type = self.visit(node.expr, scope.create_child())
if var_info is None:
self.errors.append(err.VARIABLE_NOT_DEFINED %
(node.id, self.current_method.name))
else:
if not expr_type.conforms_to(var_info.type):
self.errors.append(err.INCOMPATIBLE_TYPES %
(expr_type.name, var_info.type.name))
return expr_type
def visit(self, node: ast.LetNode, scope: Scope):
child_index = 0
for i, (_id, _type, _expr) in enumerate(node.declarations):
variable_info = scope.find_variable(_id)
if _expr is not None:
self.visit(_expr, scope.children[child_index])
child_index += 1
if _type == "AUTO_TYPE":
if variable_info.type == self.context.get_type("AUTO_TYPE"):
self.errors.append(err.INFERENCE_ERROR_ATTRIBUTE % _id)
node.declarations[i] = (_id, variable_info.type.name, _expr)
self.visit(node.expr, scope.children[child_index])
def visit(self, node: ast.MethodDeclarationNode, scope: Scope):
self.current_method = self.current_type.get_method(node.id)
return_type = self.context.get_type(node.return_type)
for i, (name, expr_body_type) in enumerate(node.params):
variable_info = scope.find_variable(name)
if variable_info.type == self.context.get_type('AUTO_TYPE'):
self.errors.append(err.INFERENCE_ERROR_ATTRIBUTE % name)
node.params[i] = (name, variable_info.type.name)
self.visit(node.body, scope)
if return_type == self.context.get_type('AUTO_TYPE'):
if self.current_method.return_type == self.context.get_type('AUTO_TYPE'):
self.errors.append(err.INFERENCE_ERROR_ATTRIBUTE % node.id)
node.return_type = self.current_method.return_type.name
def visit(self, node: ast.AssignNode, scope: Scope):
var_info = scope.find_variable(node.id)
expr_node = self.visit(node.expr, scope.create_child())
if var_info is not None:
if expr_node.type.name != 'AUTO_TYPE' and var_info.type.name == 'AUTO_TYPE':
self.graph.add_edge(expr_node, self.variables[var_info])
elif var_info.type.name != 'AUTO_TYPE' and expr_node.type.name == 'AUTO_TYPE':
self.graph.add_edge(AtomNode(self.context.get_type(var_info.type.name)), expr_node)
elif var_info.type.name == 'AUTO_TYPE' and expr_node.type.name == 'AUTO_TYPE':
# Create a cycle
self.graph.add_edge(expr_node, self.variables[var_info])
self.graph.add_edge(self.variables[var_info], expr_node)
else:
pass
return expr_node
def visit(self, node: ast.AssignNode, scope: Scope):
var_info = scope.find_variable(node.id)
if var_info.name == "self":
self.errors.append(err.SELF_IS_READONLY % (node.line, node.column))
expr_type = self.visit(node.expr, scope.create_child())
if var_info is None:
self.errors.append(
err.UNDEFINED_VARIABLE %
(node.line, node.column, node.id, self.current_method.name))
else:
if not expr_type.conforms_to(var_info.type):
self.errors.append(err.INCOMPATIBLE_TYPES %
(node.line, node.column, expr_type.name,
var_info.type.name))
return expr_type
def visit(self, node: ast.VariableNode, scope: Scope):
variable_info = scope.find_variable(node.lex)
if variable_info is not None:
return variable_info.instance
else:
return self.current_instance.get_attribute_instance(node.lex)