• Dr. Smith <iam far.out> Sep 10 2010
• Jesse Phillips <jessekphillips+D gmail.com> Sep 10 2010

Dr. Smith <iam far.out> writes:

Is there a way to preserve an array's original order, or to sort an assoc arr
by key?
With code like the following, the values of the string indices allow foreach
to needlessly re-order the array:
...
double[string][string] val;
...
foreach(string1, row; val) {
  foreach(string2, col; row) {
    writefln("%s\t%s\t%f", string1, string2, col);
  }
}

One possible way to control ordering is to add an index, like
double[int][string][string] where the int is an index.  However, I haven't yet
overcome the compiler's problem with the int.

Jesse Phillips <jessekphillips+D gmail.com> writes:

Dr. Smith Wrote:

 Is there a way to preserve an array's original order, or to sort an assoc arr
 by key?


No, Associative arrays can not preserve this for performance reasons. Though
you can do the following.


import std.algorithm;
import std.stdio;

void main() {

 double [string][string] val;

 auto keys = val.keys;
 sort(keys);
 foreach(key; keys) {
   foreach(string2, col; val[key]) {
     writefln("%s\t%s\t%f", val[key], string2, col);
   }
 }
}