digitalmars.D.bugs - [Issue 21731] New: SumType should provide convenient access to the
- d-bugmail puremagic.com (29/29) Mar 18 2021 https://issues.dlang.org/show_bug.cgi?id=21731
https://issues.dlang.org/show_bug.cgi?id=21731 Issue ID: 21731 Summary: SumType should provide convenient access to the type index Product: D Version: D2 Hardware: All OS: All Status: NEW Severity: enhancement Priority: P1 Component: phobos Assignee: nobody puremagic.com Reporter: snarwin+bugzilla gmail.com This feature was requested on the D forums [1]. It is possible to compute the type index in user code, but the implementation is a bit verbose, and easy to get wrong: ```d size_t typeIndex(Val)(Val val) if (isSumType!Val) { alias QualifiedTypes = CopyTypeQualifiers!(Val, Val.Types); return val.match!(v => staticIndexOf!(typeof(v), QualifiedTypes)); } ``` For both convenience and correctness, it would be better if this functionality were included in the `sumtype` module. [1] https://forum.dlang.org/post/ouqgmoxzlcyrfqxsrtnm forum.dlang.org --
Mar 18 2021