While most of these answers are correct to varying degrees, none of them are as succinct as I would like. Unlike most languages, for example, Python can have an else clause on a loop. Learn Python flow control to understand how you break out of while True loops. The while True: form is common in Python for indefinite loops with some way of breaking out of the loop. Here are common C infinite loops, which also work for Perl: for( ) Each language tend to have its own idiom for these constructs. Hence the infinite loop or indefinite loop. There are many algorithms where you want to process something until you find what you are looking for. Know what your language considers to be True and False for different operations and flow control to avoid many headaches later! Other languages have slightly different concepts of true / false. Python considers Truth slightly differently than Perl Truth for example. The more important part of your question is "What is while True?" is 'what is True', and an important corollary: What is false?įirst, for every language you are learning, learn what the language considers 'truthy' and 'falsey'. In fact, Python bool type is a subclass of Python's int type: > type(True) > b=bool(0.000000000000000000000000000000000001)Īnd there are "gotcha's" potentially with what you see and what the Python compiler sees: > n=0Īs a hint of how Python stores bool types internally, you can cast bool types to integers and True will come out to be 1 and False 0: > print True+0 You can use Boolean operations on bool types (at the interactive python prompt for example) and convert numbers into bool types: > print not True Formally, True is a Python built-in constant of bool type.
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