def __init__(self):
self.scope = SymbolTable(None, 'main')
class TypeChecker(NodeVisitor):
def __init__(self):
self.scope = SymbolTable(None, 'main')
def visit_BinExpr(self, node):
type1 = self.visit(node.left)
type2 = self.visit(node.right)
if ttype[node.op][type1][type2] is None:
print "Bad expression {} in line {}".format(node.op, node.line)
return ttype[node.op][type1][type2]
def visit_Const(self, node):
if re.match(r"(\+|-){0,1}(\d+\.\d+|\.\d+)", node.val):
return self.visit_Float(node)
elif re.match(r"(\+|-){0,1}\d+", node.val):
return self.visit_Integer(node)
elif re.match(r"\A('.*'|\".*\")\Z", node.val):
return self.visit_String(node)
else:
variable = self.scope.get(node.val)
if variable is None:
print "Variable {} in line {} hasn't been declared".format(node.val, node.line)
else:
return variable.type
def visit_Integer(self, node):
return 'int'
def visit_Float(self,node):
return 'float'
def visit_String(self,node):
return 'string'
def visit_Declaration(self, node):
visited_inits = self.visit(node.inits)
if visited_inits is not None:
for curr in self.visit(node.inits):
if self.scope.get_not_parent(curr[0]) is not None:
print "Variable {} in line {} has been declared earlier".format(curr[0], node.line)
else:
if node.type == curr[1] or (node.type == 'float' and curr[1] == 'int'):
self.scope.put(curr[0], VariableSymbol(curr[0], node.type))
elif node.type == 'int' and curr[1] == 'float':
print "Warning! You lost float precision in line {}".format(node.line)
self.scope.put(curr[0], VariableSymbol(curr[0], node.type))
else:
print "Type mismatch in line {}".format(node.line)
def visit_ReturnInstr(self, node):
self.scope.put('return', 'return')
if not isinstance(self.scope.get(self.scope.name), FunctionSymbol):
print "Return outside function in line {}".format(node.line)
if self.scope.parent.get(self.scope.name) is not None:
expr = self.visit(node.expr)
if self.scope.parent.get(self.scope.name).type == 'int' and expr == 'float':
print "Warning! You lost float precision in line {}".format(node.line)
elif not (self.scope.parent.get(self.scope.name).type == expr or (self.scope.parent.get(self.scope.name).type == 'float' and expr=='int')):
print "Type mismatch in line {}".format(node.line)
def visit_PrintInstr(self, node):
self.visit(node.expr)
def visit_Init(self, node):
return (node.id, self.visit(node.expr))
def visit_AssignmentInstr(self, node):
type = self.visit(node.expr)
if type is None:
return None
var_from_scope = self.scope.get(node.id)
if var_from_scope is None:
print "Variable {} in line {} hasn't been declared".format(node.id, node.line)
else:
if var_from_scope.type == 'int' and type == 'float':
print "Warning! You lost float precision in line {}".format(node.line)
self.scope.put(node.id, VariableSymbol(node.id, type))
elif not (var_from_scope.type == type or (var_from_scope.type == 'float' and type=='int')):
print "Type mismatch in line {}".format(node.line)
return (node.id, type)
def visit_ChoiceInstr(self, node):
self.visit(node.condition)
self.visit(node.instruction)
self.visit(node.else_instr)
def visit_WhileInstr(self, node):
self.visit(node.condition)
self.scope = self.scope.pushScope("loop")
self.visit(node.instruction)
self.scope = self.scope.popScope()
def visit_RepeatInstr(self, node):
self.visit(node.condition)
self.scope = self.scope.pushScope("loop")
self.visit(node.instruction)
self.scope = self.scope.popScope()
def visit_ContinueInstr(self, node):
if self.scope.name != "loop":
print "Continue outside the loop in line {}".format(node.line)
def visit_BreakInstr(self, node):
if self.scope.name != "loop":
print "Break outside the loop in line {}".format(node.line)
def visit_CompoundInstr(self, node):
self.visit(node.declarations)
self.visit(node.instructions_opt)
def visit_CastFunction(self, node):
function = self.scope.get(node.functionName)
if function is None:
print "Function {} in line {} has not been declared".format(node.functionName, node.line)
return
args_cast = self.visit(node.args)
args_scope = self.visit(function.arguments)
if len(args_cast) != len(args_scope):
print "Wrong numbers of arguments in line {}".format(node.line)
else:
for arg in args_scope:
i = args_scope.index(arg)
if arg[1] == 'int' and args_cast[i] == 'float':
print "Warning! You lost float precision in line {}".format(node.line)
elif not (arg[1] == args_cast[i] or (arg[1] == 'float' and args_cast[i] == 'int')):
print "Function arguments mismatch in line {}".format(node.line)
return function.type
def visit_ExprInBrackets(self, node):
return self.visit(node.expr)
def visit_Function(self, node):
if self.scope.get(node.id) is not None:
print "Function {} in line {} has been declared earlier".format(node.id, node.line)
else:
self.scope.put(node.id, FunctionSymbol(node.id, node.type, node.args_list_or_empty))
self.scope = self.scope.pushScope(node.id)
self.visit(node.args_list_or_empty)
self.visit(node.compound_instr)
if node.type != "void" and self.scope.get_not_parent('return') is None:
print "No return for function in line {}".format(node.line)
self.scope = self.scope.popScope()
def visit_Argument(self, node):
self.scope.put(node.id, VariableSymbol(node.id, node.type))
return (node.id, node.type)
def visit_Block(self, node):
self.scope = self.scope.pushScope("block")
self.visit(node.declarations)
self.visit(node.fundefs_opt)
self.visit(node.instructions_opt)
self.scope = self.scope.popScope()