• via Digitalmars-d-bugs (27/27) Nov 14 2016 https://issues.dlang.org/show_bug.cgi?id=16685

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

https://issues.dlang.org/show_bug.cgi?id=16685

          Issue ID: 16685
           Summary: [The D Bug Tracker]
           Product: D
           Version: D2
          Hardware: All
               URL: http://dlang.org/
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P3
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: eyal.lotem gmail.com

Failing to instantiate a template from a correctly-typed compile-time value:


struct Id { ushort value; }
enum Id x = Id(5);

struct S(ushort A) {}

// This works, as expected:
enum ushort someShortVal = 5;
alias CanCreateFromShort = S!(someShortVal);

// This works, as expected:
alias CanCreateFromTypedValue = S!(ushort(x.value));

static assert(is(typeof(x.value) == ushort));

// This surprisingly fails
alias CannotCreateFromValue = S!(x.value);

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