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digitalmars.D.bugs - [Issue 3033] New: CTFE call of non-static member function allowed inside template

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=3033

           Summary: CTFE call of non-static member function allowed inside
                    template
           Product: D
           Version: 1.045
          Platform: PC
        OS/Version: Linux
            Status: NEW
          Keywords: accepts-invalid
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: kamm-removethis incasoftware.de


From http://www.dsource.org/projects/ldc/ticket/312

The code

---
struct Struct {
   Struct method() {
      return *this;
   }
}

template Template() {
   const CONST_STRUCT = Struct().method(); // A: no error
} 
alias Template!() foo;

const CONST_STRUCT2 = Struct().method(); // B: error
---

correctly produces an error for line B "non-constant expression
(Struct()).method()" (the CTFE spec says: "4. the function may not be a
non-static member, i.e. it may not have a this pointer"), but doesn't for line
A.

Please either make both lines work and update the spec, or make A an error.

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parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=3033


Don <clugdbug yahoo.com.au> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |clugdbug yahoo.com.au
         Resolution|                            |INVALID




--- Comment #1 from Don <clugdbug yahoo.com.au>  2009-08-17 02:24:21 PDT ---
This is invalid. The template never gets instantiated (certainly its value is
never requested), so CTFE isn't involved. The alias is still OK, since it might
be used at runtime.

Try adding this line at the end:

const CONST_STRUCT3 = foo.CONST_STRUCT;

and then you'll correctly get an error.

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