[Issue 3175] New: rejects templated ref return function

Jul 14, 2009

k-foley@onu.edu

Nov 18, 2009

Luther Tychonievich

Sep 21, 2010

Sep 26, 2010

Sep 28, 2010

Sep 28, 2010

Nov 23, 2010

http://d.puremagic.com/issues/show_bug.cgi?id=3175 Summary: rejects templated ref return function Product: D Version: 2.031 Platform: Other OS/Version: Windows Status: NEW Keywords: rejects-valid Severity: normal Priority: P2 Component: DMD AssignedTo: nobody@puremagic.com ReportedBy: k-foley@onu.edu import std.stdio; // This works //ref int x(int[3] p) { return p[0]; } // This works //ref T x(T)(T[3] p) { return p[0]; } // This does not work //ref int x(size_t N)(int[N] p) if ( N > 0 ) { return p[0]; } // This does not work ref T x(T, size_t N)(T[N] p) if ( N > 0 ) { return p[0]; } int main() { auto a = [1, 2, 3]; a.x = 42; writeln( a ); return 0; } ---- $ rdmd test.d test.d(12): Error: variable test.N only parameters or foreach declarations can b e ref C:\d\dmd.2.031\dmd2\windows\bin\rdmd.exe: Couldn't compile or execute test.d. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------

November 18, 2009

[Issue 3175] rejects templated ref return function

Posted by Luther Tychonievich
in reply to k-foley@onu.edu

Permalink

Luther Tychonievich

Posted in reply to k-foley@onu.edu

Permalink

http://d.puremagic.com/issues/show_bug.cgi?id=3175


Luther Tychonievich <lat7h@virginia.edu> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |lat7h@virginia.edu
           Severity|normal                      |trivial


--- Comment #1 from Luther Tychonievich <lat7h@virginia.edu> 2009-11-18 10:30:44 PST ---
This is only a problem with template parameter deduction:

    ref int foo(int x)(int[x] v) if (x>0) { return v[0]; }

    foo!(2)([1,2]); // works
    foo([1,2]);     // gives "only parameters or foreach..." error message


It can be sidestepped by explicit template declaration:

    template foo(int x) if (x>0) {
        ref int foo(int[x] v) { return v[0]; }
    }

    foo([1,2]);     // works


While obviously not as nice as function template syntax, this workaround is not difficult to read or write and contains full functionality.


I posit the error message is wrong either way: declarations.c line 908 should
read:
    error("only function return types, parameters, and foreach declarations can
be ref");

-- 
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=3175 Shin Fujishiro <rsinfu@gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |patch Severity|trivial |major --- Comment #3 from Shin Fujishiro <rsinfu@gmail.com> 2010-09-25 18:16:35 PDT --- Patch against dmd r687. deduceFunctionTemplateMatch() must reset storage class in parameter's scope as done in matchWithInstance(). --- a/src/template.c +++ b/src/template.c @@ -887,6 +887,7 @@ MATCH TemplateDeclaration::deduceFunctionTemplateMatch(Scope *sc, Loc loc, Objec ScopeDsymbol *paramsym = new ScopeDsymbol(); paramsym->parent = scope->parent; Scope *paramscope = scope->push(paramsym); + paramscope->stc = 0; TemplateTupleParameter *tp = isVariadic(); int tp_is_declared = 0; Increased the severity as the bug has been repeatedly reported: bug 4041, bug 4446, bug 4934 and comment 2 of bug 2460. -- 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=3175 Walter Bright <bugzilla@digitalmars.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |bugzilla@digitalmars.com --- Comment #4 from Walter Bright <bugzilla@digitalmars.com> 2010-09-27 19:35:27 PDT --- Applied the patch http://www.dsource.org/projects/dmd/changeset/695 but the bug remains. -- 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=3175 --- Comment #5 from Shin Fujishiro <rsinfu@gmail.com> 2010-09-27 21:00:38 PDT --- (In reply to comment #4) > Applied the patch http://www.dsource.org/projects/dmd/changeset/695 but the bug remains. Are you saying the bug remains since the reproducing code in comment #0 doesn't compile? It's because the type of [1,2,3] has changed to dynamic int[]. Replacing 'auto' to 'int[3]' would make it compile. -- 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=3175 Don <clugdbug@yahoo.com.au> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED CC| |clugdbug@yahoo.com.au Resolution| |FIXED --- Comment #6 from Don <clugdbug@yahoo.com.au> 2010-11-23 05:15:10 PST --- (In reply to comment #5) > (In reply to comment #4) > > Applied the patch http://www.dsource.org/projects/dmd/changeset/695 but the bug remains. > > Are you saying the bug remains since the reproducing code in comment #0 doesn't compile? It's because the type of [1,2,3] has changed to dynamic int[]. Replacing 'auto' to 'int[3]' would make it compile. Indeed it does work in DMD2.050. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------

Forums