Description:
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There should be a way to check if reflected code (object, function, etc.) is from a result of eval or not.

For example;
<?php
$o = eval('class Foo { } return new Foo;');
$r = new ReflectionObject($o);
if($r->isUserDefined()) {
    $file = $r->getFilename();
    // do something with $file
}
?>

We cannot assume $file will contain a valid file path as it returns something like "/file.php:(2) eval()'d code" (rather than false imho).

Adding ReflectionObject::isSynthetic() or isEval() would be a nice feature. Please consider to return false in getFilename() for eval'd as well so "getFilename() !== false" indicates a true user defined object.