• Joseph Rushton Wakeling <joseph.wakeling webdrake.net> Aug 31 2012
• "bearophile" <bearophileHUGS lycos.com> Aug 31 2012

Joseph Rushton Wakeling <joseph.wakeling webdrake.net> writes:

Hello all,

Is it considered legit in any circumstances for popFront to take an input 
variable (e.g. a random number generator)?  Or is it required always to have no 
input variables?

Thanks & best wishes,

     -- Joe

"bearophile" <bearophileHUGS lycos.com> writes:

Joseph Rushton Wakeling:

 Is it considered legit in any circumstances for popFront to 
 take an input variable (e.g. a random number generator)?  Or is 
 it required always to have no input variables?


popFront is meant to be called by foreach, or to be verified by
the isSomething compile-time tests of std.range. In both cases if
popFront takes an argument, it doesn't work. So I think it's not
a good idea.

struct Foo {
      enum bool empty = false;
       property int front() { return 1; }
      void popFront(int x) {}
      //void popFront() {}
}
void main() {
      import std.stdio;
      foreach (i; Foo())
          writeln(i);
}


temp.d(9): Error: function temp.Foo.popFront (int x) is not
callable using argument types ()
temp.d(9): Error: expected 1 function arguments, not 0

Bye,
bearophile