Fix Issue 15891 - Compiler error when std.algorithm.cache after 2 layers of std.algorithm.map

[ghost]

Let's make the compiler happy...

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	15891	normal	Compiler error when std.algorithm.cache after 2 layers of std.algorithm.map

Testing this PR locally

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

dub fetch digger
dub run digger -- build "master + phobos#7302"

[atilaneves]

Thank you for adding the comment. Please include a link to the issue that this is fixing so someone can look it up if necessary.

[ghost]

I added the number of the issue. I hope this is what you meant with "link", because weblinks to bugreports are quite uncommon in Phobos - I couldn't find a single one...

[atilaneves]

Comment here as well please.

[atilaneves]

Ditto.

[ghost]

ping?