First Draft: Tuple Unpacking Syntax

[Timon Gehr]

On 7/27/25 08:31, Walter Bright wrote:
> This is a well written DIP. Congratulations!
> 
> The forward range tuple is pretty cool.
> 
> Let's move forward with this.
> 
> bearophile's example uses `_` as a placeholder, but I don't see it 
> mentioned in the rest of the DIP?
> ...

He had used it as a placeholder by convention, but it's just a valid 
identifier. It would not be possible to use it for two distinct 
variables in the same scope.

I.e., you can do:

```d
int _ = 2;
```

But not:

```d
int _ = 3;
int _ = 4;
```

Which would work with a true placeholder.

> For the example:
> ```
> auto arr = [tuple(1, "2"), tuple(3, "4"), tuple(5, "6")];
> 
> foreach((x, y); arr) {
>      writeln(x, " ", y); // "1 2\n3 4\n5 6"
> }
> 
> foreach((int x, string y); arr) {
>      writeln(x, " ", y);// "1 2\n3 4\n5 6"
> }
> ```
> 
> shouldn't there be a trailing \n after the 6?

Yes.