fix Issue 21801 - std.typecons.ReplaceType does not work for in parameters

[JohanEngelen]

See related: #7570

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	21801	major	std.typecons.ReplaceType does not work for in parameters

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 "stable + phobos#7937"

[Geod24]

Stable ?

[JohanEngelen]

don't know the exact dev policy. Feel free to retarget to stable.

[Geod24]

For trivial bug fixes it's better to target stable. It also means your fix will be available with the next LDC release, since Kinke usually release new minors based on the latest patch release.

[JohanEngelen]

CI is apparently broken for stable branch?

[RazvanN7]

Has there been a rebase screw-up? The bot thinks that this PR is fixing 7 issues.

[JohanEngelen]

I don't know what the bot thinks, but looks like everything is OK, just one commit on top of stable. (I've done everything through the webinterface). Thanks a lot for merging :)

[berni44]

Strange thing here. I'm getting the same failures like the failing tests, when running the tests with dmd from master instead of dmd from stable. Don't know if this helps to track down the problem...

[JohanEngelen]

Strange thing here. I'm getting the same failures like the failing tests, when running the tests with dmd from master instead of dmd from stable. Don't know if this helps to track down the problem...

The CI errors are completely unrelated to this PR.

[JohanEngelen]

#7958

[thewilsonator]

merged, please rebase.

[JohanEngelen]

rebased