c++ - What does the comma operator do? -

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what following code in c/c++?

if (blah(), 5) {     //do }

comma operator applied , value 5 used determine conditional's true/false.

it execute blah() , (presumably), comma operator employed , 5 thing used determine true/false value expression.

note , operator overloaded return type of blah() function (which wasn't specified), making result non-obvious.


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