Re: What is a sink delegate?

[Joel via Digitalmars-d-learn]

On Tuesday, 30 September 2014 at 17:27:09 UTC, Adam D. Ruppe 
wrote:
On Tuesday, 30 September 2014 at 17:22:44 UTC, Gary Willoughby 
wrote:
What is a sink delegate?

Instead of

string toString() { return "foo"; }

for example, you would use:

void toString(void delegate(string) sink) { sink("foo"); }

The sink argument there is then free to view and discard the 
data or to make a private copy using whatever scheme it desires.


How do you use that toString? Maybe an example? Below is my 
failed effort.

import std.stdio;

struct Try {
        string name;
        long age;
        
        void toString(void delegate(string) sink) {
                sink("foo");
        }
}

void main() {
        Try t = Try("Joel", 35);
        writeln(t);
}