Generates an identifier suitable to use as within a URL.
auto asSlug(R) (
if (isInputRange!R && is(typeof(R
.init .front) == dchar));
The resulting string will contain only ASCII lower case alphabetic or numeric characters, as well as dashes (-). Every sequence of non-alphanumeric characters will be replaced by a single dash. No dashes will be at either the front or the back of the result string.