大量的if，elif，else语句引起问题

Question

I am working on some code for my game and I am having an issue. I apologize in advance if this is hard to understand. The first section works fine. There is a large amount of code so I pasted it into codepad.org for easier sharing. Here's the link; http://codepad.org/kT8szBb2

Lines 108 and 142 are supposed to work together. I've tried different things like adding in this:

if True:

to try and reposition the indent level but for whatever reason it doesn't seem to work. Any suggestions work; I'm willing to try anything even if it means re-writing the entire segment. Thanks in advance.

Answer 1

Okay, I think I've found the issue. You don't quite understand how indentation works. You have code that looks like this:

if a:
    if b:
        if c:
A()
else:
    B()
    else:
        C()

This isn't how Python works. Python works with the following structure:

if a:
    A()
elif b:
    B()
elif c:
    C()

I'd really like to know where that mistake in understanding came from, because this is some extremely messy code.

Answer 2

I took the liberty of refactoring your code to be sane.

def weaponsel():
    swep = None
    #again, I'm not really sure where this is coming from or what you're doing with it
    #so it's hard to say if you should be saving the contents of swep before you run
    #the function, possibly to return if you select /return/ at the first prompt?
    while swep is None:
        print "What weapon would you like to use?"
        if weapondict["s1"] == None:
                print "Error #1: No weapons in the backpack. Contact me (Karatepig) at /hashed out for security/ and make me aware of this error."
                print "I can return you to the beginning of this checkpoint or I can end the game. Type /return/ to return or /end/ to end."
                er1=raw_input()
                if er1.lower() == "end":
                        import sys
                        sys.exit()
                elif er1.lower() == "return":
                        return None
                else: 
                        print "Sorry, I don't understand."
                        er1d()
        for weapon in ['s1','s2','s3','s4','s5','s6','s7','s8']:
            if weapondict[weapon]:
                print("The weapon {} is available".format(weapondict[weapon]))
        # as a side note, this can probably also be:
        ## for weapon in weapondict.values():
        ##     print("The weapon {} is available".format(weapon))
        # but that depends on what weapondict looks like!
        # It should be easy to expand to "types" of weapons, as well
        # using something e.g.
        ## weapondict = {"Rusty Sword":Sword(dmg=3), "Sharpened Spear":Spear(dmg=7)}
        # and testing for type(Sword) or type(Spear) based on player class or etc.
        # but you'd need to build classes for this to work, e.g.
        ## class Weapon(object):
        ##     def __init__(self,dmg=1):
        ##         self.dmg = dmg
        ##
        ## class Sword(Weapon):
        ##     self.type = "Sword"
        ##     self.dmgType = "Slashing"
        ##
        ## class Spear(Weapon):
        ##     self.type = "Spear"
        ##     self.dmgType = "Thrusting"
        # then you can have slashing do more damage to lightly armored targets and
        # thrusting do more damage to heavily armored targets and etc. Even writing
        # methods to attack characters based on their equipped weapons. This is a
        # PRIME example of where OOP will get you big results fast!

        weapon=raw_input()
        if weapon.lower() not in weapondict.values():
            print "Sorry, I don't understand that.\n\n"
            continue

        print("You have selected the {}".format(weapon))
        swepd1 = raw_input("Is that what you want? ")
        if swepd1.lower() in ("y","yes"): swep = weapon

If you have any questions, don't hesitate to ask. I haven't actually tested this, so syntax errors may abound. I'm fairly certain it works as intended, however. As a side note -- where does weapondict come from? It's not in your code anywhere and it's likely that this function can't see it (unless you defined it earlier as global weapondict .)

Answer 3

There is really no need for all those if 's. You should absolutely be using a for loop.

weapons = { 1:'sword', 2:'mace', 3:'bow'}

for wep in weapons:
    print('the {} is available'.format(weapons[wep]))

outputs:

the sword is available
the mace is available
the bow is available