Fix Issue 19738 - std.range.choose assignment breaks @safe-ty

[thewilsonator]

cc @WalterBright @dnadlinger

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	19738	regression	std.range.choose assignment breaks @safe-ty

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• Regression or critical bug fixes should always target the stable branch. Learn more about rebasing to stable or the D release process.

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Testing this PR locally

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dub fetch digger
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[dnadlinger]

Thanks!

[thewilsonator]

This is a master regression, so no stable.

[thewilsonator]

Stupid question: why does this fail, when the static assert in https://run.dlang.io/is/Vjjcjf doesn't?

[WalterBright]

Should remove @trusted from the declaration of opAssign

[thewilsonator]

Whoops! That'd certainly do it!

[thewilsonator]

Hmm, this seems to break https://github.com/dlang/phobos/blob/master/std/algorithm/iteration.d#L6181-L6201

on all except
"".substitute("","").equal(""); (line 6185)

""w.substitute(""w,""w).equal(""w); (line 6190), and

""d.substitute(""d,""d).equal(""d); (line 6195)

[thewilsonator]

Seems to come from either https://github.com/dlang/phobos/blob/master/std/algorithm/iteration.d#L5791 or https://github.com/dlang/phobos/blob/master/std/algorithm/iteration.d#L5800

[ghost]

Is there any progress on this?

[thewilsonator]

Superseded by #7348