1.  Is the best way to hash a uint[] slice

2.  How do you do it?

On Thursday, 23 July 2015 at 11:15:46 UTC, Enjoys Math wrote:
> 1.  Is the best way to hash a uint[] slice
>
> 2.  How do you do it?

IIRC, std.digest functions take ubyte[] as input, so to hash a uint[] I would do the following:

    void main(string[] args)
    {
        import std.conv;
        import std.digest.md;

        int[] a   = [1, 2, 3, 4, 5];
        auto  md5 = new MD5Digest();

        md5.put(a.to!(ubyte[]));

        auto hash = md5.finish();
        writeln(hash);
    }

On Thursday, 23 July 2015 at 11:49:05 UTC, cym13 wrote:
> On Thursday, 23 July 2015 at 11:15:46 UTC, Enjoys Math wrote:
>> 1.  Is the best way to hash a uint[] slice
>>
>> 2.  How do you do it?
>
> IIRC, std.digest functions take ubyte[] as input, so to hash a uint[] I would do the following:
>
>     void main(string[] args)
>     {
>         import std.conv;
>         import std.digest.md;
>
>         int[] a   = [1, 2, 3, 4, 5];
>         auto  md5 = new MD5Digest();
>
>         md5.put(a.to!(ubyte[]));
>
>         auto hash = md5.finish();
>         writeln(hash);
>     }

Thanks.  That worked.   Here's my code:

module hashtools;
import std.conv;
import std.digest.md;

string uintSliceToHash(const uint[] slice) {
    auto  md5 = new MD5Digest();
    md5.put(slice.to!(ubyte[]));
    return md5.finish().to!(string);
}

unittest {
    import std.stdio;
    uint[] slice = [1,2,3,4];
    writeln(uintSliceToHash(slice));
}

On Thursday, 23 July 2015 at 12:10:04 UTC, Enjoys Math wrote:
> On Thursday, 23 July 2015 at 11:49:05 UTC, cym13 wrote:
>>     [...]
>
> Thanks.  That worked.   Here's my code:
>
> module hashtools;
> import std.conv;
> import std.digest.md;
>
> string uintSliceToHash(const uint[] slice) {
>     auto  md5 = new MD5Digest();
>     md5.put(slice.to!(ubyte[]));
>     return md5.finish().to!(string);
> }
>
> unittest {
>     import std.stdio;
>     uint[] slice = [1,2,3,4];
>     writeln(uintSliceToHash(slice));
> }

Actually, uint[] seems to be hashable:

    import std.stdio;
    int[uint[]] aa;
    aa[[1,2,3]] = 5;
    writeln(aa[[1,2,3]]);

WORKS

All types are hashable and for your own structs and classes you can redefine opHash

On Thursday, July 23, 2015 12:56:13 Temtaime via Digitalmars-d-learn wrote:
> All types are hashable and for your own structs and classes you can redefine opHash

It's toHash, actually, but yeah.

- Jonathan M Davis