Skip iteration of array_map function if IF statement True

Question

Is there a way to break or continue an iteration of the built-in method array_map() as you would in a normal for loop?

For example:

array_map(function (String s) {
    if (condition is met){
        continue;
    }
    return stuff;
}, $array_to_map);

Notus

But wouldn't this defeat the whole purpose? – Eudo

You should probably use array_filter. What is your input and output? – Shawnee

Possible duplicate of Jump out from array_walk – Bury

@Shawnee input is class object of strings output is array of strings – Notus

@Notus It's helpful if you include that in your post. I recommend showing a minimal reproducible example, otherwise, this looks like an x-y problem because it appears like you're attempting to use a tool in a way it wasn't meant to be used. – Shawnee

thats what i assumed, but I wanted to be sure. So a foreach statement would be better? – Notus

Sorry, I can't say because I'm not sure what problem you're trying to solve. – Shawnee

Answer 1

No. array_map returns an array the same length as the original so you can't skip an item. i.e. Something needs to be returned on each iteration.

You could use array_filter to remove certain items.

Hoyle

Answer 2

$results = array_map(function (String s) {
    if (condition is met){
        //do stuff 
    } else {
        return false;
    }
    return stuff;
}, $array_to_map);

$results will then contain a array with the orignal number of elements in it as the $array_to_map, only with array elements set to false when the condition failed

then do.

$array_with_elements_remove = array_filter($results, function($e){
    return $e; //when this value is false the element is removed.
});

Occurrence

Answer 3

You can emulate continue by simply returning the original value.

array_map(function($var){
  if(condition)
    return $var; //continue
  return $transformedValue;
}, $arr);

However there would be no way to actually break (except disgusting things like using a StopIteration exception class)

Guillen

I don't think that 2nd return will happen. – Metcalfe

Sure, but why post something like that? It's misleading. The manual on return states "If called from within a function, the return statement immediately ends execution of the current function, and returns its argument as the value of the function call. return also ends the execution of an eval() statement or script file." - If you get a downvote, it wouldn't have been mine, just saying. – Metcalfe

What bothers me is that you're bugged with the return statements not the fact that neither condition nor $transformedValue is actually declared. – Guillen

"Bothers" you? huh? – Metcalfe

@FunkFortyNiner omitting the braces on a single-statement block is bad practice, but it's permissible. – Dickinson

Answer 4

You can try sth like this:

$newArrayWithIds = [];

array_map(function (int $id) use ($newArrayWithIds): void {
   if($id === 0) {
     return;
   }
   $newArrayWithIds[] = $id; 
}, $yourArrayWithIds);

Gilthead