More D newb questions.

[Janice Caron]

On 06/05/2008, Walter Bright <newshound1 at digitalmars.com> wrote:
>  There is no way opCat can do both jobs.

I completely agree. And there is another reason that this is a bad idea:

People observe that

    array ~ array = array
    array ~ char = array
    char ~ array = array

(assuming array is an array of chars, of course), and then suppose
that the fourth case should also yield array.

    char ~ char = array

But.... Suppose I replace the built in array type with my own custom
container, Array. Then I can override opCat and opCat_r to give me

    MyArray ~ MyArray = MyArray
    MyArray ~ char = MyArray
    char ~ array = MyArray

However, there is no way I can persuade my custom container to give me
the effect:

    char ~ char = MyArray

because the bottom line is, a container needs to know about its
elements, but elements do not need to know about their container.
Allowing ~ to create arrays from primitive types would give built-in
arrays an unfair advantage over custom arrays, and that alone should
be enough reason to disallow it.