C++ function returning bool not executed -


this question has answer here:

given c++ function foo:

bool foo();

and following lines of code

bool some_bool = false; some_bool = some_bool , foo();

i observed foo() not called although might have side-effects. name of behavior , compiler-dependent?

this called short-circuit evaluation.

in example, some_bool false , statement some_bool && foo() going false. there never need evaluate foo().

note standard c/c++ , not compiler dependent can lead unperformed code you've discovered.

a better way of writing code is:

bool some_bool = false; bool foo_result = foo(); some_bool = some_bool && foo_result;

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