array_merge_unique

[binaryfire]

Description

Combining array_unique and array_merge is very common. I think a performance-optimized array_merge_unique method would be greatly appreciated by a lot of people.

Edit: My main point is that having a single method which covers this common use case would make code cleaner (regardless of performance).

[nielsdos]

If you write it like this: array_unique(array_merge(...)) then the engine already optimizes it by avoiding copies since #11060 landed on 8.3.
I'm not sure providing these kinds of optimizations as functions directly to the user is all that useful. My personal opinion is that the engine should transparently handle this and the user shouldn't have to care about this.

[binaryfire]

That's great to know. I probably shouldn't have mentioned performance to be honest- it's more about having a single method that covers a very common use case. It would make things much cleaner.

[nielsdos]

it's more about having a single method that covers a very common use case. It would make things much cleaner.

The question is then how many more combinations we would need to create. If we create a single combination then it quickly can become a slippery slope to add tons and tons of combinations.
Usually the idea in API design is to have smaller, separate methods/functions that do one thing and can be combined by calling them in a nested way.

In any case if you want this functionality, I'd suggest mailing the mailing list and pursuing an RFC: https://wiki.php.net/rfc/howto

[iluuu1994]

My personal opinion is that the engine should transparently handle this and the user shouldn't have to care about this.

I'd agree. There are virtually endless ways to combine internal functions. Of course, some combinations are more common than others, but it seems more useful to improve speed of function calls and parameter passing, rather than introducing more functions just for performance.

#12461 is an attempt to do this for internal functions. Maybe we can explore improvemenets for user functions in the future. I remember an attempt from Bob, I will have a look at this again soon.

[github-actions]

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