• via Digitalmars-d-bugs (21/22) Jul 11 2017 https://issues.dlang.org/show_bug.cgi?id=17634

via Digitalmars-d-bugs <digitalmars-d-bugs puremagic.com> writes:

https://issues.dlang.org/show_bug.cgi?id=17634

          Issue ID: 17634
           Summary: variadic overload of
                    std.algorithm.searching.countUntil should return which
                    needle was found
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody puremagic.com
          Reporter: greensunny12 gmail.com

Find does this already:

https://dlang.org/phobos/std_algorithm_searching.html#.find.4

 A tuple containing haystack positioned to match one of the needles and also
the 1-based index of the matching element in needles (0 if none of needles
matched, 1 if needles[0] matched, 2 if needles[1] matched...). The first needle
to be found will be the one that matches. If multiple needles are found at the
same spot in the range, then the shortest one is the one which matches (if
multiple needles of the same length are found at the same spot (e.g "a" and
'a'), then the left-most of them in the argument list matches).

It would be convenient if countUntil would behave the same, but it's probably
too late to change the return type, so the only way left is adding an optional
`out` parameter.

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