pygame代码中的错误

Question

# INTIALISATION
import pygame, math, sys
from pygame.locals import *
screen = pygame.display.set_mode((1024, 768))
car = pygame.image.load('car.png')
clock = pygame.time.Clock()
k_up = k_down = k_left = k_right = 0
speed = direction = 0
position = (100, 100)
TURN_SPEED = 5
ACCELERATION = 2
MAX_FORWARD_SPEED = 10
MAX_REVERSE_SPEED = ­5
BLACK = (0,0,0)
while 1:
    # USER INPUT
    clock.tick(30)
    for event in pygame.event.get():
        if not hasattr(event, 'key'): continue
        down = event.type == KEYDOWN     # key down or up?
        if event.key == K_RIGHT: k_right = down * ­5
        elif event.key == K_LEFT: k_left = down * 5
        elif event.key == K_UP: k_up = down * 2
        elif event.key == K_DOWN: k_down = down * ­2
        elif event.key == K_ESCAPE: sys.exit(0)     # quit the game
    screen.fill(BLACK)
    # SIMULATION
    # .. new speed and direction based on acceleration and turn
    speed += (k_up + k_down)
    if speed > MAX_FORWARD_SPEED: speed = MAX_FORWARD_SPEED
    if speed < MAX_REVERSE_SPEED: speed = MAX_REVERSE_SPEED
    direction += (k_right + k_left)
    # .. new position based on current position, speed and direction
    x, y = position
    rad = direction * math.pi / 180
    x += ­speed*math.sin(rad)
    y += ­speed*math.cos(rad)
    position = (x, y)
    # RENDERING
    # .. rotate the car image for direction
    rotated = pygame.transform.rotate(car, direction)
    # .. position the car on screen
    rect = rotated.get_rect()
    rect.center = position
    # .. render the car to screen
    screen.blit(rotated, rect)
    pygame.display.flip()
    enter code here

我遇到的错误是：在文件 race1.py 的第13行有一个非ASCII字符 '\xc2'，但没有声明编码；详细信息请查看 http://www.python.org/peps/pep-0263.html

我不太明白这个错误是什么，以及该怎么解决它？

Answer 1

在第13行，你有一个非ASCII字符。Python不接受源文件中的UTF-8编码，除非你在文件的开头加上一条特别的注释：

# encoding: UTF-8

Answer 2

正如Greg所说，你的代码里有一个非ASCII字符——在第13行的5前面看起来像一个减号的符号。这个符号叫做“软连字符”。在你的代码中，有几个地方用这个符号代替了减号。你需要把这些符号删掉，换成真正的减号。

你上面的代码没有显示出这个字符。我也不知道为什么。当我把它复制粘贴到文本编辑器里时，我能看到这个字符。

如果你在代码的顶部加一个编码注释，比如：

# -*- coding: utf-8 -*-

那么你会因为这个“软连字符”而出现语法错误。所以你需要把它们全部替换成减号。（这样你就不需要在代码顶部加编码注释了。）