how hash_t toHash() works?

[Ivan Kazmenko]

> one more question
> What is the type of cont?
>
> auto cont = redBlackTree !("a.key < b.key", true, MyRecord) ();
>
> I want to use this as a property in a class and i can't use 
> there auto keyword... I tried different types but it did not 
> work.

For me, the following declaration works:

-----
import std.functional;
...
	RedBlackTree !(MyRecord, binaryFun!"a.key < b.key", true) cont;
...
	cont = redBlackTree !("a.key < b.key", true, MyRecord) ();
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I admit it could have been easier to figure out.  For example, 
"writeln (typeof (cont).stringof);" just prints "RedBlackTree" 
which is not enough for a proper declaration.  I've inferred the 
right declaration from the following lines in container.d:

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/++ Ditto +/
auto redBlackTree(alias less, bool allowDuplicates, E)(E[] 
elems...)
     if(is(typeof(binaryFun!less(E.init, E.init))))
{
     //We shouldn't need to instantiate less here, but for some 
reason,
     //dmd can't handle it if we don't (even though the template 
which
     //takes less but not allowDuplicates works just fine).
     return new RedBlackTree!(E, binaryFun!less, 
allowDuplicates)(elems);
}
-----