A little of coordination for Rosettacode

[Andrea Fontana]

On Tuesday, 19 March 2013 at 15:55:19 UTC, ixid wrote:
> I was just looking at the Rosetta code for prime decomposition 
> and it seems bugged to me, wanted to make sure as you seem to 
> be the one coordinating these things:
>
> http://rosettacode.org/wiki/Prime_decomposition#D
>
> This will potentially return a 1 in the list of primes which is 
> a bug as 1 isn't prime.

You're right. I think the right code for decompose is this:

T[] decompose(T)(T n) /*pure nothrow*/ {
	T[] res;
	for (T i = 2; n % i == 0;) {
		res ~= i;
		n /= i;
	}
	for (T i = 3; n != 1; i += 2) { // ----- Changed condition
		while (n % i == 0) {
			res ~= i;
			n /= i;
		}
	}
         // ----- Removed concat here
	return res;
}