• =?UTF-8?B?Ik3DoXJjaW8=?= Martins" (13/13) Jul 25 2014 Hello!
• bearophile (23/29) Jul 25 2014 Currently D array operations can't be used for that kind of

=?UTF-8?B?Ik3DoXJjaW8=?= Martins" <marcioapm gmail.com> writes:

Hello!

I started exploring D today and one of the things that caught my 
attention was the "array operations" feature.

While playing around and writing some code with it, I came across 
a problem I wasn't able to find a solution for. The following is 
a simple example of the assignment array operator to initialize 
an array.

float[10] a;
a[] = uniform(0.0f, 1.0f);

This is going to set all values to the result of a single call to 
uniform();

Is there a way to express my intent that I want one result per 
array element?

"bearophile" <bearophileHUGS lycos.com> writes:

Márcio Martins:

 float[10] a;
 a[] = uniform(0.0f, 1.0f);

 This is going to set all values to the result of a single call 
 to uniform();

 Is there a way to express my intent that I want one result per 
 array element?

Currently D array operations can't be used for that kind of 
usage. So you have to use a normal foreach loop:

void main() {
     import std.stdio, std.random;

     float[10] a;

     foreach (ref x; a)
         x = uniform01;

     a.writeln;
}


Or you can also use ranges, in a functional style:


void main() {
     import std.stdio, std.range, std.random, std.algorithm;

     float[10] a;

     a
     .length
     .iota
     .map!(_ => uniform01)
     .copy(a[]);

     a.writeln;
}

Bye,
bearophile