Defining a static array with values in a range

[anony via Digitalmars-d-learn]

On Thursday, 22 January 2015 at 05:56:40 UTC, tcak wrote:
> I want to define alphanumeric characters in an easy way. 
> Something like that:
>
> char[] arr = ['a'..'z', 'A'..'Z', '0'..'9'];
>
> Though above example doesn't work. Is there any easy way to do 
> this?
>
> I am trying to do something like EBNF definitions. So, I do not 
> want to use loops, or define every single thing one by one by 
> hand.

There are convenient constants defined in std.ascii.

import std.ascii;
string arr = lowercase ~ uppercase ~ digits;

// also 'std.ascii.letters' gives ('A' .. 'Z' ~ 'a' .. 'z')