Question 5.22: Repeating Instructions Until Some Condition Changes You need......
Repeating Instructions Until Some Condition Changes
You need to repeat some program code until something changes.
Step-by-Step
Use the Python while statement. The while statement repeats its nested commands until its condition becomes false. The following example will stay in the loop until the user enters X for exit:
| >>> answer = ” >>> while answer != ‘X’: … answer = input(‘Enter command:’) … Enter command:A Enter command:B Enter command:X >>> |
Discussion
Note that the preceding example uses the input command as it works in Python 3. To run the example in Python 2, substitute the command raw_input for input.
See Also
If you just want to repeat some commands a number of times, see Recipe 5.20.
If you are trying to repeat commands for each element of a list or dictionary, then see Recipes 6.7 or 6.15, respectively.
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