https://issues.dlang.org/show_bug.cgi?id=21650
--- Comment #2 from Steven Schveighoffer ---
I don't think having both overloads would break any code. Types don't match
values, values don't match types.
parse(Target, Source, Flag!"doCount" doCount)(Source rng) will match existing
uses that specify the source range type explicitly
parse(Target, Flag!"doCount" doCount, Source)(Source rng) will match new uses
that want to use IFTI to detect the Source range type.
What was discussed in that thread is inserting the flag in *existing*
functions. I'm talking about adding overloads to address the new usage.
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