class Interpreter(object):
pc = [0, 0]
stack = []
direction = '>'
string_mode = False
running = False
height = 25
width = 80
debug = False
def __init__(self, content):
parser = Parser(content)
self.__datasource = Terminal()
self.__parser = parser
self.__program = parser.get_program()
def execute(self, debug=True):
self.debug = debug
self.running = True
if self.debug:
print self.__program
while self.running:
self.step()
self.__increment_pc()
print
def __pop_two(self):
return (self.__pop(), self.__pop())
def __push(self, i):
return self.stack.append(i)
def __pop(self):
return self.stack.pop()
def __increment_pc(self):
delta = {
'>': [0, 1],
'<': [0, -1],
'^': [-1, 0],
'v': [1, 0],
}.get(self.direction, [0, 0])
self.pc = [self.pc[0] + delta[0], self.pc[1] + delta[1]]
# Wrap around the y axis.
if self.pc[0] < 0 and self.direction == '^':
self.pc[0] = self.height
if self.pc[0] > self.height and self.direction == 'v':
self.pc[0] = 0
# Wrap around the x axis.
if self.pc[1] < 0 and self.direction == '<':
self.pc[1] = self.width
if self.pc[1] > self.width and self.direction == '>':
self.pc[1] = 0
def step(self):
x, y = self.pc[0], self.pc[1]
try:
instruction = self.__program[x][y]
except IndexError:
instruction = {'kind': 'NOP', 'value': ' '}
self.op(instruction['kind'], instruction['value'])
def op(self, kind, value):
if self.string_mode and kind != 'STRING_MODE':
self.__push(ord(value))
else:
# State changers.
if kind == 'STRING_MODE':
self.string_mode = not self.string_mode
if kind in ['MOVE_RIGHT', 'MOVE_LEFT', 'MOVE_UP', 'MOVE_DOWN']:
self.direction = value
if kind == 'MOVE_RANDOM':
self.direction = random.choice(['v', '^', '<', '>'])
if kind == 'NUMBER':
self.__push(int(value))
if kind == 'SKIP':
self.__increment_pc()
## Conditionals.
if kind == 'COND_X':
self.direction = '>' if self.__pop() == 0 else '<'
if kind == 'COND_Y':
self.direction = 'v' if self.__pop() == 0 else '^'
# Operations.
if kind == 'ADDITION':
(a, b) = self.__pop_two()
self.__push(a + b)
if kind == 'MULTIPLICATION':
(a, b) = self.__pop_two()
self.__push(a * b)
if kind == 'DUP':
try:
val = self.stack[-1]
except IndexError:
val = 0
self.__push(val)
if kind == 'SUBTRACTION':
(a, b) = self.__pop_two()
self.__push(b - a)
if kind == 'SWAP':
(a, b) = self.__pop_two()
self.__push(a)
self.__push(b)
if kind == 'GREATER_THAN':
a, b = self.__pop_two()
self.__push(1 if b > a else 0)
if kind == 'LOGICAL_NOT':
a = self.__pop()
self.__push(1 if a == 0 else 0)
if kind == 'MODULO':
(a, b) = self.__pop_two()
self.__push(a % b)
if kind == 'INT_DIVISION':
(a, b) = self.__pop_two()
self.__push(b / a)
# IO.
if kind == 'OUTPUT_INT':
self.__datasource.write(str(self.__pop()))
if kind == 'OUTPUT_CHAR':
self.__datasource.write(chr(self.__pop()))
if kind == 'INPUT_CHAR':
self.__push(ord(self.__datasource.next()))
if kind == 'INPUT_INT':
self.__push(int(self.__datasource.next()))
# Reflection.
if kind == 'GET':
instruction = self.__program[self.__pop()][self.__pop()]
self.__push(ord(instruction['value']))
if kind == 'PUT':
y, x = self.__pop_two()
v = self.__pop()
self.__program[y][x] = self.__parser.lex_char(chr(v))
if kind == 'END':
self.running = False
if self.debug:
print x, y, instruction, self.stack
def __init__(self, content):
parser = Parser(content)
self.__datasource = Terminal()
self.__parser = parser
self.__program = parser.get_program()
