# RFC: Change behaviour of array sort functions to return a copy of the sorted array

- Status: Withdrawn
- Authors: Gina Peter Banyard girgias@php.net
- Date: 2024-10-20
- Version: 0.1
- Target: PHP 8.5
- Implementation: TBD
- Original: https://wiki.php.net/rfc/array-sort-return-array
- Page: https://externals.io/rfc/array-sort-return-array
- More for agents: search with https://externals.io/search.md?q={query} · RFCs at https://externals.io/rfc.md · JSON API at https://externals.io/api · documentation at https://externals.io/llms.txt

## Votes

### Accept Change behaviour of array sort functions to return a copy of the sorted array RFC? (closed)

Yes: 0 · No: 0

## Discussions on the mailing list

- [\[RFC\] Change behaviour of array sort functions to return a copy of the sorted array](https://externals.io/message/125809.md) — started on 2024-10-20, 24 messages

---

## Introduction

The PHP array sort functions take the array to sort as a by-reference array to sort the array in place. However, since PHP 5.6 these function have only ever returned `true`.

Moreover, it would only return `false` (or `null`) prior to this version in case of a memory allocation failure. This effectively means the return values of these functions are useless. Similarly, `array_walk()`, `array_walk_recursive()`, and `shuffle()` have only ever returned `true`(or in case of type errors `null` or `false` which are proper `TypeError`s as of PHP 8.0) since at least PHP 5.3. One last array function that now only returns `true` since PHP 8.0 is `array_multisort()`, when all warnings and false returns were converted to `ValueError`s and `TypeError`s.

This behaviour is annoying as it makes writing code in a functional way more cumbersome and tedious. Indeed, when working with higher order functions (e.g. `array_map()`), one cannot just use these functions as callbacks and must instead wrap them in a closure which returns the sorted array.

## Proposal

Change the return value of:

- `sort()`
- `rsort()`
- `asort()`
- `arsort()`
- `ksort()`
- `krsort()`
- `natsort()`
- `natcasesort()`
- `usort()`
- `uasort()`
- `uksort()`
- `array_multisort()`
- `shuffle()`
- `array_walk()`
- `array_walk_recursive()`

from `true` to a copy of the `array` that is sorted, traversed, or shuffled.

This operation is effectively “for free” as we just increment the reference count of the sorted array by one.

## Backward Incompatible Changes

Sorting an empty array and checking the return value of one of the `sort()` functions would now be falsy rather than `true`.

## Unaffected PHP Functionality

The functions continue to take the first parameter by-reference and do the sorting in-place.

The sort methods from the SPL `ArrayObject` class are not affected by this change.

## Version

Next minor version, PHP 8.5.

## Vote

As per the voting RFC a yes/no vote with a 2/3 majority is needed for this proposal to be accepted.

Voting started on 2024-XX-XX and will end on 2024-XX-XX.

**Vote: Accept Change behaviour of array sort functions to return a copy of the sorted array RFC?** — Yes: 0 · No: 0 (closed)

## References

Internals discussion thread: <https://externals.io/message/125809>