logical operands on strings

[Erik van Velzen]

I would like to do this:

     string one = x"315c4eeaa8b5f8aaf9174145bf43e1784b";
     string two = x"c29398f5f3251a0d47e503c66e935de81230b59b7a";
     string three = one ^ two;


The closests I've been able to get is:

     string three = xor(one, two);

     string xor(string one, string two) {
         int len = min(one.length, two.length);
         string result;
         for(int i=0; i<len; i++) {
             result ~= one[i] ^ two[i];
         }
         return cast(string)result;
     }

Question 1: is there a more elegant way to implement the function 
xor? (foreach-ish or std.algorithm)


Then I tried to add operator overloading:

     string opBinary(string op)(string lhs, string rhs) {
         static if( op == "^" )
             return xor(lhs, rhs);
         else static assert(false, "operator not possible");
     }

But it doesn't invoke this function.

Question 2: how would I implement "^" for strings?