Is there a way to extend a trait in PHP?

Question

I want to use functionality of an existing trait and create my own trait on top of it only to later apply it on classes.

I want to extend Laravel SoftDeletes trait to make SaveWithHistory function, so it will create a copy of a record as a deleted record. I also want to extend it with record_made_by_user_id field.

Possible duplicate of [Extend Traits with Classes in PHP?](http://stackoverflow.com/questions/10056520/extend-traits-with-classes-in-php) — Mihai Matei, Oct 28 '16 at 06:20
https://stackoverflow.com/a/37687295/470749 is a good answer. — Ryan, Nov 13 '18 at 17:55

score 181 · Accepted Answer · edited Oct 16 '18 at 09:31

181

Yes, there is. You just have to define new trait like this:

trait MySoftDeletes 
{
    use SoftDeletes {
        SoftDeletes::saveWithHistory as parentSaveWithHistory;
    }

    public function saveWithHistory() {
        $this->parentSaveWithHistory();

        //your implementation
    }
}

edited Oct 16 '18 at 09:31

molerat

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answered Oct 28 '16 at 06:25

Filip Koblański

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Just for reference, to searchers, here is further information: https://www.php.net/manual/en/language.namespaces.importing.php – That Realty Programmer Guy Aug 20 '19 at 21:18
In this context, you might find the following resource helpful: https://stackoverflow.com/questions/39820753/how-does-insteadof-keyword-in-a-trait-work – J. D. Oct 16 '19 at 10:57
https://stackoverflow.com/a/37687295/470749 shows another example of extending traits. – Ryan Oct 18 '19 at 21:41

score 13 · Answer 2 · answered Nov 25 '20 at 16:33

I have different approach. ParentSaveWithHistory is still applicable method in this trait so at least should be defined as private.

trait MySoftDeletes
{
    use SoftDeletes {
        saveWithHistory as private parentSaveWithHistory; 
    }

    public function saveWithHistory()
    {
        $this->parentSaveWithHistory();
    }
}

Consider also 'overriding' methods in traits:

use SoftDeletes, MySoftDeletes {
    MySoftDeletes::saveWithHistory insteadof SoftDeletes;
}

This code uses method saveWithHistory from MySoftDeletes, even if it exists in SoftDeletes.

Is there a way to extend a trait in PHP?

2 Answers2

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