Function List.length
Returns the length of the list, in terms of number of elements.
size_t length() const pure nothrow @nogc @property scope @safe;
Examples
List!(int) list = null;
assert(list .length == 0);
list .append(42);
assert(list .length == 1);
list .append(123);
assert(list .length == 2);
list .clear();
assert(list .length == 0);