How to use "or"

[tewe]

Hi!
I'm not a total beginner in python, I know the basics if you know what I mean. Right now I am working on a text-base adventure game. I want there to be two ways of typing the decision in.

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while True:
                answer = raw_input("You have to decide. Do you want to continue, or not")
                answer = answer.lower()

                if answer == ("continue") or ("i want to continue"):
                        game()
                        break

Now the game accepts all inputs. It doesn't have to be one of them. It even accepts "bajskorv". It works while there is only one alternative. "continue" or "i want to continue".

I don't understand what is wrong. By the way, I am using Python 2.7.3.
I really appreciate your help!

[DougieLawson]

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if (answer == "valid answer#1") or (answer == "valid answer#2"):
    do_something_positive()
else:
    do_something_else()

[tewe]

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if (answer == "valid answer#1") or (answer == "valid answer#2"):
    do_something_positive()
else:
    do_something_else()

I don't really understand what you mean. But if you mean that I need an else statement you're wrong. There is an else statement but I didn't include it in the part of code I pasted in.

[DougieLawson]

You need to test variable against value on both sides of the OR statement.

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if (variable == "value1") OR (variable == "value2"):
    do_something_for_a_positive_compare()

[tewe]

You need to test variable against value on both sides of the OR statement.

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if (variable == "value1") OR (variable == "value"):
    do_something_for_a_positive_compare()

Sorry for being a bit rude. Thanks Doug! I thinks this is the third time you fix my problems.

Thank you!

[elParaguayo]

For anyone else reading this, I think it may be useful to explain why Dougie's answer is correct.

If you look at the docs for Boolean operations, there's an example that says:

Operation: x or y
Result: if x is false, then y, else x

This means you have the following possibilities:

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True or True -> True
True or False -> True
False or True -> True
False or False -> False

In the code example above, the test is evaluated as follows:

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#Assuming answer is something other than "continue"
answer == ("continue") or ("i want to continue")
#is the same as:
False or ("i want to continue")
#is the same as
False or True
#is the same as
True

This part of the docs explains why the string "I want to continue" is the same as True.

Dougie's amendments mean that, instead of returning True for the string, python compares answer to "I want to continue" and evaluates it as True or False as appropriate.

[billio]

Just to indicate an alternative way of doing this avoiding the "or" :

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if answer in ["continue","i want to continue"] :
    # do whatever you want to do

or in a different situation :

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if answer not in ["quit","stop","halt","bye"] :
    # carry on