D-Programming-Language/phobos — pull request #932 by monarchdodra (2012-11-07 10:05:04+00:00)
Title: Insert dropBack, more examples of drop

This introduces `dropBack`. While using bidirectional ranges, such as when interfacing with `std.container.DList`, I've found that `dropBack` was painfully needed.

Besides, if we have `popFrontN`, `popBackN` and `drop`, then we need `dropBack`.

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Inserted the signature `dropFront`, out of completeness of implementation and symmetry with `dropBack`. This is only an alias though, and documented as such.

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Added some bidir-range (DList) examples, where using `drop` is really more than just a convenience, it is an indispensable tool. This helps highlight how and where to use `drop[|Front|Back]`

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Also, relativelly unrelated fix: `popBackN` now request `isBidirectionalRange`