%u Wrote:
> %u Wrote:
>
> > I found a slideshow called 'The Expressiveness of Go' recently. The conclusions are:
> >
> > * Go is not a small language but it is an expressive and comprehensible one.
> >
> > * Expressiveness comes from orthogonal composition of constructs.
> >
> > * Comprehensibility comes from simple constructs that interact in easily understood ways.
> >
> > * Build a language from simple orthogonal constructs and you have a language that will be easy and productive to use.
> >
> > * The surprises you discover will be pleasant ones.
> >
> > ----
> >
> > Is D orthogonal? Could it be more orthogonal? Two things come to my mind: removing special cases and making widely used things first class. For data types this means that they have literals, can be given to functions and returned from functions. I made a small test and found that the discoveries aren't pleasant to me:
> >
> >
> > class A {}
> > class B : A {}
> > class C : A {}
> >
> > template T(A...) { alias A T; }
> >
> > void main() {
> > auto a = true ? new B : new C;
> > // these don't work - why?
> > // auto b = [new B, new C];
> > // auto c = { return [1: new B,2: new C]; };
> >
> > T!(int,int) e = (1,2);
> > e = T!(3,4);
> >
> > // ah - so (1,2) syntax on initialization, T!(1,2) when assigning!
> > T!(int,int) d = T!(1,2);
> >
> > e = d;
> >
> > // tuples aren't first class, why?
> > // auto f = { return e; };
> > }
>
> I then test this in Scala REPL:
>
> scala> class A; class B extends A; class C extends A
> defined class A
> defined class B
> defined class C
>
> scala> val a = List(new B,new C)
> a: List[A] = List(B@1f18cd5, C@154f6ff)
>
> scala> val b = Map(1 -> new B, 2 -> new C)
> b: scala.collection.immutable.Map[Int,A] = Map((1,B@14512e), (2,C@1ddbcb1))
>
> scala> var e = (1,2)
> e: (Int, Int) = (1,2)
>
> scala> e = (3,4)
> e: (Int, Int) = (3,4)
>
> scala> val d = (1,2)
> d: (Int, Int) = (1,2)
>
> scala> e = d
> e: (Int, Int) = (1,2)
>
> scala> val f = () => e
> f: () => (Int, Int) = <function0>
>
> scala> f()
> res0: (Int, Int) = (1,2)