#32 let (x,y) = ...

[Peter Wilson]

Make access to tupple contents easier. I believe Groovy
has this feature:

Taken from manual.html:Example 7.2. Method returning
several values using a tuple

#1 usage improvement: allow local variables on tupple
returns:

declaration:
(int, int) minMax(int x, int y) = x < y ? (x, y) : (y, x);
use:
(x, y) = minMax(3,5); // not very convincing for this
function.
println("(" + x + ", " + y + ")");

#2 usage improvement: allow local variables on tupple
arguments:
void printTuple((int x, int y) tuple)
{
// /** Declare two local variables, and assign to each
the //corresponding value
// in the tuple.
// */
// (int x, int y) = tuple;

println("(" + x + ", " + y + ")");
}

[Daniel Bonniot]

Logged In: YES
user_id=88952

I'd like to ask for some clarifications:

For #1:
You can already do
(x, y) = minMax(3,5);
provided that x and y are previously declared. You can also
declared them at that spot with:
(int x, int y) = minMax(3,5);

Is that you want to be able to declare them without
specifying the type? I believe this could be useful, but a
specific syntax should be used to make that clear.
Consistently, this should be
let (x, y) = minMax(3,5);
and
var (x, y) = minMax(3,5);
for constant and variables, respectively.

Does this correspond to what you expected?

For #2:
Unless I'm mistaken, what you are asking for is already
possible:
void printTuple((int x, int y) tuple)

You can even leave the name 'tuple' out since it is not used:
void printTuple((int x, int y))

Is that so? Is this missing from the documentation?

[Nobody/Anonymous]

Logged In: NO

My misunderstanding. - From your reply, the current usage
is fine.

However, example 7.2 in the User's Manual is misleading as
it fails to use feature #2. It should be updated, or shown
as an alternative.

[Daniel Bonniot]

Logged In: YES
user_id=88952

OK, I updated the manual accordingly.

I leave this report open, as I believe it would be useful to
support the 'let (x,y) = ...' syntax.