Question

foreach ( functionWithComplicatedComputationReturningAnArray() as $key => $value)

Will the above code call the function more than once?

And generally, are there rules in this regard, about PHP language constructs accepting function calls as parameters?

Thanks

Gidi

Answer 1

No, it will be called once. This:

foreach (functionWithComplicatedComputationReturningAnArray() as $key => $value) {
  ...
}

is semantically equivalent to:

$tmp = functionWithComplicatedComputationReturningAnArray();
foreach ($tmp as $key => $value) {
  ...
}

(ignoring the fact that the second one will leak the value outside the foreach loop).