I'm using PHP and have a pair of arrays of associative arrays, along the lines of:
{foo: [{id: 1, title: "one"}, {id: 2, title: "two"}]}
{bar: [{id: 2, title: "DEUX"}, {id: 3, title: "TROIS"}]}
I want to exclude any item from the first array where its ID appears in the second, so what in a sane language might be expressed as:
foo = foo.Where(x => !bar.Any(y => x.ID == y.ID));
The PHP manual appears to point to array_udiff as the tool for this job, so that I might use:
array_udiff($foo, $bar, function($x, $y) { ... });
with some suitable function that compares $x['id'] with $y['id'].
I was expecting the function to be called with each possible pair of $x and $y, i.e. such that a function($x, $y) { print $x['title'] . ", " . $y['title']; return 0;} would output something like:
- one, DEUX
- one, TROIS
- two, DEUX
- two, TROIS
with $x always a value from the first array and $y one from the second.
What's actually being passed in is a complete mish-mash of values from each array which makes no sense to me at all, e.g.
- two, one
- TROIS, DEUX
- two, TROIS
- two, one
Can anyone please explain what's going on?
Complete code producing the above output:
$foo[] = array('id' => 1, 'title' => 'one');
$foo[] = array('id' => 2, 'title' => 'two');
$bar[] = array('id' => 2, 'title' => 'DEUX');
$bar[] = array('id' => 3, 'title' => 'TROIS');
array_udiff($foo, $bar, function($x, $y) { print $x['title'] . ", " . $y['title'] . "\n"; return 0;});
Thanks.
