Regarding type deduction

2012-09-17 Thread bearophile 
Do you think it's useful and possible to extend the D type 
inference (deduction) for templates to support something like 
this (I know there are different ways to do this in D)?



struct Tree1 {
static struct Node { int x; }
}
struct Tree2 {
static struct Node { int x, y; }
}
void foo(T)(T.Node n1, T.Node n2) {} // ***
void main() {
Tree1.Node n1, n2;
foo(n1, n2);
}


(I am asking this because nested types are becoming increasingly 
common in D code.)


Bye,
bearophile

Re: Regarding type deduction

2012-09-17 Thread Jesse Phillips 

On Monday, 17 September 2012 at 14:54:48 UTC, bearophile wrote:
Do you think it's useful and possible to extend the D type 
inference (deduction) for templates to support something like 
this (I know there are different ways to do this in D)?



struct Tree1 {
static struct Node { int x; }
}
struct Tree2 {
static struct Node { int x, y; }
}
void foo(T)(T.Node n1, T.Node n2) {} // ***
void main() {
Tree1.Node n1, n2;
foo(n1, n2);
}


(I am asking this because nested types are becoming 
increasingly common in D code.)


Bye,
bearophile


I can't say I've ever thought to have such. But it seems it could 
simplify something. Though I'd think the syntax:


Void foo(T: T.Node) (...

Or more proper.