[Issue 7815] New: Mixin template forward reference (?) regression

http://d.puremagic.com/issues/show_bug.cgi?id=7815

           Summary: Mixin template forward reference (?) regression
           Product: D
           Version: D2
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: regression
          Priority: P2
         Component: DMD
        AssignedTo: nobody@puremagic.com
        ReportedBy: code@klickverbot.at


--- Comment #0 from klickverbot <code@klickverbot.at> 2012-04-03 10:08:27 PDT ---
DMD 2.058 accepted the following snippet, while DMD c2824d43 executes the else branch of the static if. In there, though, instantiating the template will (apparently) just work fine.

---
mixin template Helpers() {
  alias typeof(this) This;

  static if (is(Flags!This)) {
    Flags!This flags;
  } else {
    // DMD will happily instantiate the allegedly
    // non-existent Flags!This here. (!)
    pragma(msg, __traits(derivedMembers, Flags!This));
  }
}

template Flags(T) {
  mixin({
    string defs;
    foreach (name; __traits(derivedMembers, T)) {
        defs ~= "bool " ~ name ~ ";\n";
    }
    if (defs.length > 0) {
      return "struct Flags {" ~ defs ~ "}";
    } else {
      return "";
    }
  }());
}

struct Move {
  int a;
  mixin Helpers!();
}

enum a = Move.init.flags; // isSetFlags should exist.
---

(Note that while the above code is probably not the minimal possible example needed to trigger the bug, it has been reduced beyond repair as far as its original intent goes, so don't try to make sense of it in that regard.)

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http://d.puremagic.com/issues/show_bug.cgi?id=7815 --- Comment #1 from github-bugzilla@puremagic.com 2012-04-05 21:07:38 PDT --- Commit pushed to master at https://github.com/D-Programming-Language/dmd https://github.com/D-Programming-Language/dmd/commit/7a81d73021c456fd546cb241f40420717d2ec365 fix Issue 7815 - Mixin template forward reference (?) regression -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7815 Walter Bright <bugzilla@digitalmars.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED CC| |bugzilla@digitalmars.com Resolution| |FIXED -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7815 David Simcha <dsimcha@yahoo.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|RESOLVED |REOPENED Resolution|FIXED | --- Comment #3 from David Simcha <dsimcha@yahoo.com> 2012-04-07 17:22:21 PDT --- I reduced the case where it's still failing, reopened. enum Closure { Matrix } struct BasicMatrix { mixin Operand!( Closure.Matrix ); } template Operand( Closure closure_ ) { alias closure_ closure; } struct Expression( string op_, Lhs, Rhs = void ) { enum lhsClosure = closureOf!Lhs; } template closureOf( T ) { enum closureOf = T.closure; } alias Expression!("+", BasicMatrix) Foo; test.d(18): Error: no property 'closure' for type 'BasicMatrix' test.d(14): Error: template instance test.closureOf!(BasicMatrix) error instantiating test.d(21): instantiated from here: Expression!("+",BasicMatrix) test.d(21): Error: template instance test.Expression!("+",BasicMatrix) error instantiating -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7815 --- Comment #4 from Walter Bright <bugzilla@digitalmars.com> 2012-04-07 18:06:42 PDT --- Please, the original two bugs were fixed and are fixed. A new bug should entered for new bugs, not reopening fixed ones. For next time. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7815 Walter Bright <bugzilla@digitalmars.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Severity|regression |normal --- Comment #5 from Walter Bright <bugzilla@digitalmars.com> 2012-04-07 18:18:42 PDT --- This new case fails also on dmd 2.058, so it is not a regression. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7815 --- Comment #6 from Walter Bright <bugzilla@digitalmars.com> 2012-04-07 18:19:31 PDT --- Reduced test case: ----------------------- enum Closure { Matrix } struct BasicMatrix { mixin Operand!( Closure.Matrix ); } template Operand( Closure closure_ ) { alias closure_ closure; } alias BasicMatrix.closure Foo; -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7815 --- Comment #9 from klickverbot <code@klickverbot.at> 2012-04-08 10:10:43 PDT --- The original code I reduced the test case from still doesn't work either, will report a new bug once I managed to reduce it again. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------

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