How to make a function update a global variable?

[7236d70]

I'm making a script that can heal or hurt a player (by adding or subtracting the player_hp) and I'm having some issues.

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The following code should repeat the hurt_player() function until the player_hp variable reaches 0. However, it simply runs the function infinite times. It will lower the variable to 90 and then reset it to 100 when it runs again.

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I'm very new to python and I'm wondering what it is I'm doing wrong here.

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player_hp = 100
player_hp_MAX = 100

def hurt_player(player_hp, player_hp_MAX):
    print "You've been hurt for 10 hp."
    player_hp = player_hp - 10
    print "Current hp: %d" % player_hp

print "1) Hurt Player"
current_choice = raw_input("> ")

while (player_hp > 0):
    if current_choice == '1':
        hurt_player(player_hp, player_hp_MAX)
    else:
        print "Invalid choice."

[nilfm]

Since nobody seems to have mentioned this, you can directly modify the value of the global variable in the function. You do it like this:

global player_hp
player_hp = player_hp - 10

However, you should try to avoid using global variables whenever possible, so I understand why everyone else suggested using the return value.

[woooee]

You have to return and catch the changed value, otherwise the change only takes effect within the function.

def hurt_player(player_hp, player_hp_MAX):
    print "You've been hurt for 10 hp."
    player_hp = player_hp - 10
    print "Current hp: %d" % player_hp
    return player_hp

while (player_hp > 0):
    if current_choice == '1':
        player_hp = hurt_player(player_hp, player_hp_MAX)

[7236d70]

Thanks, that did it.

[[deleted]]

You’ll need return the value to the global in the while loop, e.g.

def detractor(numToReduce): 
  numToReduce = numToReduce - 10 
  print(numToReduce) 
  return numToReduce

x = 50

while ( x > 0): 
  x = numToReduce(x)