def test_assignment_complex(self):
parser = Parser()
tree = parser.run("x = y = 3")
self.assertEqual(tree.op, Token(lexems.ASSIGNMENT, lexems.ASSIGNMENT))
self.assertEqual(tree.right.op,
Token(lexems.ASSIGNMENT, lexems.ASSIGNMENT))
self.assertEqual(tree.left.val, Token(lexems.LETTER, 'x'))
def test_fn_def_add(self):
parser = Parser()
tree = parser.run("fn add x y => x + z")
self.assertEqual(Token(lexems.LETTER, "add"), tree.name)
self.assertEqual(
[Token(lexems.LETTER, "x"),
Token(lexems.LETTER, "y")], tree.arguments)
self.assertEqual(Token(lexems.PLUS, lexems.PLUS), tree.definition.op)
def test_fn_def(self):
parser = Parser()
tree = parser.run("fn avg x y => (x + y) / 2")
self.assertEqual(Token(lexems.LETTER, "avg"), tree.name)
self.assertEqual(
[Token(lexems.LETTER, "x"),
Token(lexems.LETTER, "y")], tree.arguments)
self.assertEqual(Token(lexems.DIVIDE, lexems.DIVIDE),
tree.definition.op)
def test_fn_def_echo_call_no_def(self):
parser = Parser()
tree = parser.run("fn echo x => x")
self.assertEqual(Token(lexems.LETTER, "echo"), tree.name)
self.assertEqual([Token(lexems.LETTER, "x")], tree.arguments)
self.assertEqual(Token(lexems.LETTER, "x"), tree.definition.val)
with self.assertRaises(Exception) as context:
tree = parser.run("echo1 11")
def test_adding(self):
parser = Parser()
tree = parser.run("1 + 7")
self.assertEqual(tree.op, Token(lexems.PLUS, lexems.PLUS))
self.assertEqual(tree.left.val, Token(lexems.DIGIT, 1))
self.assertEqual(tree.right.val, Token(lexems.DIGIT, 7))
def test_fn_def_echo(self):
parser = Parser()
tree = parser.run("fn echo x => x")
self.assertEqual(Token(lexems.LETTER, "echo"), tree.name)
self.assertEqual([Token(lexems.LETTER, "x")], tree.arguments)
self.assertEqual(Token(lexems.LETTER, "x"), tree.definition.val)
def test_bad_fn_def(self):
parser = Parser()
tree = parser.run("fn avg => (x + y) / 2")
self.assertEqual(Token(lexems.LETTER, "avg"), tree.name)
def test_brackets(self):
parser = Parser()
tree = parser.run("(1 + 7) * 5")
self.assertEqual(tree.op, Token(lexems.MULTIPLY, lexems.MULTIPLY))
self.assertEqual(tree.right.val, Token(lexems.DIGIT, 5.0))
def test_multiply(self):
parser = Parser()
tree = parser.run("1 + 7 * 5")
self.assertEqual(tree.op, Token(lexems.PLUS, lexems.PLUS))
self.assertEqual(tree.left.val, Token(lexems.DIGIT, 1.0))
def test_fn_def_echo_call_no_args(self):
parser = Parser()
tree = parser.run("fn echo => 2")
self.assertEqual(Token(lexems.LETTER, "echo"), tree.name)
def __init__(self):
self.parser = Parser()
self.variables = {}
self.functions = {}
class Interpreter(NodeVisitor):
def __init__(self):
self.parser = Parser()
self.variables = {}
self.functions = {}
def input(self, line):
self.parser.clear()
tree = self.parser.run(line)
return self.visit(tree, None)
def visit_BinaryNode(self, node, var_values, check):
if check:
self.visit(node.left, var_values, check)
self.visit(node.right, var_values, check)
return None
if node.op.type == PLUS:
return self.visit(node.left, var_values) + self.visit(
node.right, var_values)
elif node.op.type == MINUS:
return self.visit(node.left, var_values) - self.visit(
node.right, var_values)
elif node.op.type == MULTIPLY:
return self.visit(node.left, var_values) * self.visit(
node.right, var_values)
elif node.op.type == DIVIDE:
return self.visit(node.left, var_values) / self.visit(
node.right, var_values)
elif node.op.type == PERCENT:
return self.visit(node.left, var_values) % self.visit(
node.right, var_values)
elif node.op.type == ASSIGNMENT:
left = self.visit(node.left, var_values)
val = self.visit(node.right, var_values)
self.variables[left] = val
return val
def visit_LiteralNode(self, node, var_values, check):
if node.val.type == LETTER:
vardict = self.variables
if var_values != None:
vardict = var_values
if node.val.value not in vardict:
raise Exception("Undefined variable {}".format(node.val.value))
return vardict[node.val.value]
if check:
return None
if node.val.type == EOF:
return node.val.value
return node.val.value
def visit_VariableDefinitionNode(self, node, var_values, check):
if node.val.value in self.functions:
raise Exception("Already defined variable {}".format(
node.name.value))
return node.val.value
def visit_FunctionDefinitionNode(self, node, var_values, check):
if node.name.value in self.variables:
raise Exception("Already defined variable {}".format(
node.name.value))
self.functions[node.name.value] = node
# calc parameters
local_varvalues = {}
for (i, argnode) in enumerate(node.arguments):
local_varvalues[argnode.value] = None
if len(local_varvalues) != len(node.arguments):
raise Exception("Variable name duplication")
# check variables
self.visit(node.definition, local_varvalues, True)
return ""
def visit_FunctionCallNode(self, node, var_values, check):
if node.name.value not in self.functions:
raise Exception("Undefined function {}".format(node.name.value))
function_node = self.functions[node.name.value]
#calc parameters
local_varvalues = {}
for (i, argnode) in enumerate(function_node.arguments):
local_varvalues[argnode.value] = self.visit(
node.arguments[i], None)
return self.visit(function_node.definition, local_varvalues)