• ciechowoj (9/9) Feb 15 2016 It there a way to change how writeln converts structs to strings?
• cym13 (15/25) Feb 15 2016 Just define a toString method, it will be used by .to!string

ciechowoj <keepitsimplesirius gmail.com> writes:

It there a way to change how writeln converts structs to strings? 
I read in the documentation it uses to!string to convert the 
struct. Is there a way to overload to!string for my own type?

Let say I have:

struct Point {
     int x, y;
}

and I want writeln(Point(3, 4)); to print "[3, 4]" instead of 
"Point(3, 4)".

cym13 <cpicard openmailbox.org> writes:

On Monday, 15 February 2016 at 12:03:44 UTC, ciechowoj wrote:
 It there a way to change how writeln converts structs to 
 strings? I read in the documentation it uses to!string to 
 convert the struct. Is there a way to overload to!string for my 
 own type?

 Let say I have:

 struct Point {
     int x, y;
 }

 and I want writeln(Point(3, 4)); to print "[3, 4]" instead of 
 "Point(3, 4)".

Just define a toString method, it will be used by .to!string

     struct Point {
         int x;
         int y;

         string toString() {
             import std.format: format;
             return format("[%d, %d]", x, y);
         }
     }

     void main(string[] args) {
         import std.stdio: writeln;

         auto p = Point(3, 4);
         p.writeln; // [3, 4]
     }