On 19 Jun, 2013, at 1:04 AM, Patrick Schaaf <b...@bof.de> wrote:
> > > var_dump(array_filter(['foo', '', 'bar'], 'strlen', true)); > > > > Warning: strlen() expects exactly 1 parameter, 2 given in - on line 1 > > > > Not only do we trigger the error handler (a large enough array causes a > > performance issue), but we also get back an empty array as a result. That's > > BC and performance loss that's simply unacceptable, so defaulting the > > behavior to pass the key is simply out of the question. > > Existing code won't pass that third, true, argument to array_filter(), and > thus will not break. > > Nevertheless, I'd say go with a new array_filter_key() function, because that > permits using existing one-parameter functions like that strlen as a > callback, instead of forcing two-parameter callback functions. > I've mirrored the behaviour of this feature from JavaScript as much as possible (but obviously without passing the array itself as the third argument). As such I don't feel there's a need to introduce yet another function just so that the key is passed as the first argument. And to use both key and value forces the developer to use closures instead of just any callback unless this means the second argument passed to the callback is the array :) > Another alternative might be to go with a third argument to array_filter(), > but make that an integer with ORable constants ARRAY_FILTER_KEY, > ARRAY_FILTER_VAL - only one of them set calls with a single argument, both > set call with two arguments. > I see some potential here, albeit a bit more magical :) Let's see how the discussion progresses. > best regards > Patrick
