[API Proposal]: System.String.RSplit

[mikeronayne]

Background and motivation

Python exposes this as rsplit (tests showing behavior here).

Note that Python's maxsplit parameter has a bit different semantics than C#'s Split's count. C#'s RSplit should use C#'s Split's count semantics.

API Proposal

This should behave exactly like the System.String.Split overloads that accept count, except we start counting delimiters from the right instead of the left.

API Usage

"ABC-DEF-GHI".RSplit('-', count: 2) returns ["ABC-DEF", "GHI"]

Alternative Designs

Instead of adding a new RSplit method, I could see this also being implemented as a new StringSplitOptions.

Risks

No response

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[teo-tsirpanis]

Extending StringSplitOptions sounds like a better idea than adding a new method (which should be called something like SplitRight).

[MichalPetryka]

SplitRight

Or SplitEnd.