https://issues.dlang.org/show_bug.cgi?id=20756

          Issue ID: 20756
           Summary: ImplicitConversionTargets ignores interface
                    inheritance
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: minor
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: default_357-line@yahoo.de

Repro:

interface A { }
interface B : A { }

static assert(is(ImplicitConversionTargets!B == AliasSeq!(A)));

Expected:

AliasSeq!(A)

Got:

AliasSeq!()

To add, TransitiveBaseTypeTuple (which ImplicitConversionTargets uses) also doesn't support interface parameters.

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