Make toDelegate safe for function pointers

[Bolpat]

No description provided.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	18171	enhancement	std.functional.toDelegate should be usable in @safe

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + phobos#8769"

[dkorpel]

Why is there a new branch for function pointers, is the final else case obsolete now?

• $(LI Does not work with @safe functions.)

This line is no longer accurate now

[Bolpat]

Why is there a new branch for function pointers, is the final else case obsolete now?

Because toDelegate works with any callable, the else branch cannot be @safe in general. To be @safe for function pointers, toDelegate needed a specific branch (or it looked like the best solution to me).

[Bolpat]

• $(LI Does not work with @safe functions.)

This line is no longer accurate now

That should have been a review comment.

[dkorpel]

That should have been a review comment.

I can't comment on code not in the diff

[dkorpel]

Because toDelegate works with any callable

There's now branches for delegate, function, and opCall, what remaining cases does toDelegate support?

[dkorpel]

Ping @Bolpat

[dkorpel]

Ping @Bolpat

[Bolpat]

Sorry, I was absent for a while. I looked into the failed checks and didn’t understand what’s wrong.

Should I force-push?

[PetarKirov]

@Bolpat yes, please rebase & force-push.

[dkorpel]

Also, please answer #8769 (comment)