On 2/27/13 5:12 PM, H. S. Teoh wrote:
The most basic, non-templated implementation of "tap" would look like
this:
Object tap (alias func) (Object o)
{
func(o);
return o;
}
What would a templated version add to this functionality?
class Point
{
int x;
int y;
}
Point createPoint ()
{
return (new Point).tap!((p) { p.x = 3; p.y = 4 });
}
I guess I'm skeptical about the value of using tap in this context,
since you could just call the function on the object, then set its
values, then return it. So this is just syntactic sugar.
Tap is nice when you want to print-debug something and you have a chain
of calls:
auto foo = x.map!(...).reduce!(...).nWayUnion!(...);
Now something is not working correctly and you want to see what's after
the "reduce!" step:
auto foo = x.map!(...).reduce!(...).tap!(r) { writefln(r);
}).nWayUnion!(...);
Otherwise you'd have to break it in many lines and then put them back
together.
