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cyrus+php at boadway dot ca
3 years ago
There's some inconsistent behaviour associated with PHP 5.5.3's finally and return statements. If a method returns a variable in a try block (e.g. return $foo;), and finally modifies that variable, the /modified/ value is returned. However, if the try block has a return that has to be evaluated in-line (e.g. return $foo+0;), finally's changes to $foo will /not/ affect the return value.

[code]
function returnVariable(){
    $foo = 1;
    try{
        return $foo;
    } finally {
        $foo++;
    }
}

function returnVariablePlusZero(){
    $foo = 1;
    try{
        return $foo + 0;
    } finally {
        $foo++;
    }
}

$test1 = returnVariable(); // returns 2, not the correct value of 1.
$test2 = returnVariablePlusZero(); // returns correct value of 1, but inconsistent with $test1.
[/code]

It looks like it's trying to be efficient by not allocating additional memory for the return value when it thinks it doesn't have to, but the spec is that finally is run after try is completed execution, and that includes the evaluation of the return expression.

One could argue (weakly) that the first method should be the correct result, but at least the two methods should be consistent.

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