初学者问题：从 Python 中的函数返回一个布尔值
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Beginner question: returning a boolean value from a function in Python
提问by matt
I'm trying to get this rock paper scissors game to either return a Boolean value, as in set player_winsto True or False, depending on if the player wins, or to refactor this code entirely so that it doesn't use a while loop.
I'm coming from the sysadmin side of the world, so please be gentle if this is written in the wrong style.
I have tried a few things, and I understand TIMTOWTDI, and would just like some input.
我试图让这个石头剪刀布游戏返回一个布尔值，如设置player_wins为 True 或 False，取决于玩家是否获胜，或者完全重构此代码，使其不使用 while 循环。我来自世界的系统管理员方面，所以如果以错误的方式编写，请保持温和。我已经尝试了一些东西，我了解 TIMTOWTDI，并且想要一些输入。
Thanks.
谢谢。
import random
global player_wins
player_wins=None
def rps():
player_score = 0
cpu_score = 0
while player_score < 3 and cpu_score < 3:
WEAPONS = 'Rock', 'Paper', 'Scissors'
for i in range(0, 3):
print "%d %s" % (i + 1, WEAPONS[i])
player = int(input ("Choose from 1-3: ")) - 1
cpu = random.choice(range(0, 3))
print "%s vs %s" % (WEAPONS[player], WEAPONS[cpu])
if cpu != player:
if (player - cpu) % 3 < (cpu - player) % 3:
player_score += 1
print "Player wins %d games\n" % player_score
else:
cpu_score += 1
print "CPU wins %d games\n" % cpu_score
else:
print "tie!\n"
rps()
I'm trying to do something like this:
我正在尝试做这样的事情：
print "%s vs %s" % (WEAPONS[player], WEAPONS[cpu])
if cpu != player:
if (player - cpu) % 3 < (cpu - player) % 3:
player_score += 1
print "Player wins %d games\n" % player_score
if player_score == 3:
return player_wins==True
else:
cpu_score += 1
print "CPU wins %d games\n" % cpu_score
if cpu_score == 3:
return player_wins==False
else:
print "tie!\n"
采纳答案by asthasr
Ignoring the refactoring issues, you need to understand functions and return values. You don't need a global at all. Ever. You can do this:
忽略重构问题，您需要了解函数和返回值。你根本不需要全局。曾经。你可以这样做：
def rps():
# Code to determine if player wins
if player_wins:
return True
return False
Then, just assign a value to the variable outside this function like so:
然后，只需为该函数外的变量赋值，如下所示：
player_wins = rps()
It will be assigned the return value (either True or False) of the function you just called.
它将被分配您刚刚调用的函数的返回值（True 或 False）。
After the comments, I decided to add that idiomatically, this would be better expressed thus:
在评论之后，我决定用惯用语来补充，这样表达会更好：
def rps():
# Code to determine if player wins, assigning a boolean value (True or False)
# to the variable player_wins.
return player_wins
pw = rps()
This assigns the boolean value of player_wins(inside the function) to the pwvariable outside the function.
这将player_wins（函数内部）的布尔值分配给函数pw外部的变量。
回答by Cpt. eMco
Have your tried using the 'return' keyword?
您是否尝试过使用“return”关键字？
def rps():
return True
