[Issue 21022] std.range.only does not work with const

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=21022

Mathias LANG <pro.mathias.lang at gmail.com> changed:

           What    |Removed                     |Added
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           Keywords|                            |industry
                 CC|                            |pro.mathias.lang at gmail.com

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