http://d.puremagic.com/issues/show_bug.cgi?id=7838
--- Comment #2 from bearophile_h...@eml.cc 2012-04-06 10:09:17 PDT --- (In reply to comment #1) > My understanding is that you would usually put a static assert with > isInputRange, or a more specific template from std.range immediately after the > struct. This is an example program: import std.range, std.bigint; struct Powers { int m; BigInt n; this(int m_) { this.m = m_; } const bool empty = false; BigInt front() { return n ^^ m; } void popFront() { n += 1; } } static assert(isInputRange!Powers); void main() {} If I compile it with DMD 2.059beta: ...>dmd -property -run temp.d temp.d(10): Error: static assert (isInputRange!(Powers)) is false So it gives me no hint where the problem is. A built-in error message is supposed to be more precise. As alternative, maybe there is a way to add focused error messages inside a isInputRangeVerify template to be used to verify that an input range is correct, that uses pragma(msg) or better ctWriteln. > How is DMD supposed to know that that struct is suppose to be a range > otherwise? I see, it's a problem. So here we are talking more about a probabilistic compiler tip. If the class/struct contains a popFront and front and empty methods then the programmer probably meants it to be a range. Thank you for your answer. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------