On Friday, 20 August 2021 at 15:12:25 UTC, james.p.leblanc wrote:
Greetings,
I have a user created struct, let's call this "**fakeArray**":
For all intents and purposes fakeArray behaves like an array
(or slice, I guess).
(i.e. It has a number of operator overloadings, and *foreach*
extensions implemented.)
I have a fairly large number of function in a module that
accept arrays (or slices).
These are implemented as:
**auto foo(T)(T[] x) { ... }**
So, foo will accept "official" arrays and slices.
What is the easiest way to coerce all my functions to also
accept my fakeArray?
The most straightforward way would be to change your functions
from accepting only `T[]` to accepting either `T[]` or
`fakeArray`. For example:
```d
import std.traits: isDynamicArray;
// assuming `fakeArray` is a template struct/class
enum isFakeArray(T) = is(T == fakeArray!U, U);
auto foo(Array)(Array x)
if (isDynamicArray!Array || isFakeArray!Array)
{
// ...
}
```
The `if (...)` part there is a [template constraint][1]. It means
that the template can only be instantiated when the condition
evaluates to `true`.
[1]: https://dlang.org/spec/template.html#template_constraints
