Revive std.range.slide from the dead

[wilzbach]

This is a revival of std.range.slide ... finally!

History

std.range.slide was introduced in #4027 and I delayed its release in #5614 as at the time of the merge I didn't have to work on it.

Why was it needed to rework this function before its release?

tl;dr: the implementation of withFewerElements was broken for Yes.withFewerElements.
(see #5614 for details).

Changes

It's hard make an exact summary of the changes,

• added proper handling for Yes.withPartial
• renamed withFewerElements to withPartial (shorted & clearer name)
• made all tests function use withPartial explicitly
• extensive tests (2/3 of the size)
• more comments and explanation (another big chunk of this functions size)

I apologize for this diff being so big, but most changes are the extended test coverage.

[dlang-bot]

Thanks for your pull request, @wilzbach!

Bugzilla references

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[JackStouffer]

One thing I would like to see before this gets merged is to cut down on the number of tests, as this is most likely the most tested range function by far. There are tons of places here where many different cases are tested where one or two would have sufficed.

[wilzbach]

One thing I would like to see before this gets merged is to cut down on the number of tests, as this is most likely the most tested range function by far.

Removed the number of tests by 300 lines (and addressed your other points).

[JackStouffer]

Looks good. I'll wait a week to allow other commentary and merge if there's no comments.