http://d.puremagic.com/issues/show_bug.cgi?id=3197
Summary: Minor fixes and additions to std.traits Product: D Version: future Platform: All OS/Version: All Status: NEW Severity: enhancement Priority: P2 Component: Phobos AssignedTo: nob...@puremagic.com ReportedBy: bugzi...@kyllingen.net Created an attachment (id=430) --> (http://d.puremagic.com/issues/attachment.cgi?id=430) Patch for traits.d (svn rev. 1242) These are just some small fixes and additions to std.traits that I've found useful, and I would very much like to see them included in Phobos. Firstly, I've attached a patch against traits.d (svn rev. 1242) which does the following: - Made ParameterTypeTuple work with structs/classes with opCall. Updated doc comment to reflect this and added unittest. - I've changed the code of ReturnType so that the "argument has no return type" error is emitted instead of just a template instantiation failure whenever a struct/class without an opCall is given as the argument. Secondly, here are two things I'd like to see in std.traits: /** Get the type of the elements of an array. * Example: * --- * int[][] foo; * ElementType!foo bar; // bar is declared as int (not int[]) * --- */ template ElementType(alias dg) { alias ElementType!(typeof(dg)) ElementType; } /// ditto template ElementType(T : T[]) { alias ElementType!T ElementType; } template ElementType(T) { alias T ElementType; } unittest { static assert (is(ElementType!(int[]) == int)); real[][] foo; static assert (is(ElementType!foo == real)); } /** Detect whether T is a callable type, i.e. a function, * a pointer to a function, a delegate, a struct with an opCall, * a pointer to a struct with an opCall, or a class with * an opCall. */ template isCallable(T) { static if (is(T == return)) enum isCallable = true; else static if (is(typeof(&T.opCall) == return)) enum isCallable = true; else enum isCallable = false; } unittest { static assert (isCallable!(int delegate())); struct Bar { int opCall() { return 0; } } static assert (isCallable!Bar); static assert (!isCallable!int); } -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------