string-int[] array

[FG via Digitalmars-d-learn]

On 2015-03-08 at 20:26, Meta wrote:
> On Sunday, 8 March 2015 at 18:57:38 UTC, Kagamin wrote:
>> http://dpaste.dzfl.pl/2c8d4a7d9ef0 like this.
>
> What in the world is that code doing? I'm having a hard time wrapping my head around this.

It's a trick to reuse string internals to store an int.
A string is a struct with two values (length, ptr).
ivalue(i) is used to set ptr = i and length = 0.

Except that with this solution you will confuse empty strings with ints.
You could give such strings special treatment by replacing:

     this(string s){ svalue=s; }

with:

     this(string s){ svalue=s; if (!s.length) svalue = cast(string)(cast(char*)0)[X..X]; }
     // where X is some magic int value to mark that we are dealing with an empty string,

you'd still be confused if someone actually wanted to store the X value.