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digitalmars.D - Structs with a disabled default ctor can't pass as ranges

reply Andrej Mitrovic <andrej.mitrovich gmail.com> writes:
I've ran into a bit of an issue. isInputRange is defined like this:

template isInputRange(R)
{
    enum bool isInputRange = is(typeof(
    {
        R r;              // can define a range object
        if (r.empty) {}   // can test for empty
        r.popFront();     // can invoke popFront()
        auto h = r.front; // can get the front of the range
    }()));
}

But this will fail for structs which have a disabled default ctor. Was
this planned?
Sep 24 2011
parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Sat, 24 Sep 2011 17:33:37 -0400, Andrej Mitrovic  
<andrej.mitrovich gmail.com> wrote:


 I've ran into a bit of an issue. isInputRange is defined like this:

 template isInputRange(R)
 {
     enum bool isInputRange = is(typeof(
     {
         R r;              // can define a range object
         if (r.empty) {}   // can test for empty
         r.popFront();     // can invoke popFront()
         auto h = r.front; // can get the front of the range
     }()));
 }

 But this will fail for structs which have a disabled default ctor. Was
 this planned?



I don't think this was planned.

I think this should fix it:

R r = R.init;

-Steve
Sep 26 2011