• Bill Cox (29/29) Jan 25 2003 Hi.

Bill Cox <bill viasic.com> writes:

Hi.

I saw in the 'Future' section of the D documentation the following:

    1.   A generic way to iterate across a collection, i.e. a foreach 
construct instead of a for loop. A reverse iterator will be needed, too.

In the language I wrote over Christmas, I added support for itterators 
in a way that I like better than the support in C++ or Java.  IMO 
Itterators are important enough to justify new syntax.  Here's what I did:

In a class, you declare a method like:

Class Foo {
     Bar firstBar;
     loop forward(inout Bar bar) {
         for(bar = firstBar; bar != null; bar = bar.nextFooBar) {
             doLoop;
         }
     }
}

Class Bar {
     Bar nextFooBar;
     Foo owner;
}

The foreach statement looks like:

testLoop(Foo foo)
{
     Bar bar;
     foreach(foo.forward, bar) {
         /* do something with bar here */
     }
}


Bill Cox