New Issue: How should tuple declarations interact with multiple variable declarations?

19340, "mppf", "How should tuple declarations interact with multiple variable declarations?", "2022-03-02T14:57:09Z"

This issue asks a questions about how tuple declarations should combine with multiple variable declarations. See also Variables — Chapel Documentation 1.25 and Tuples — Chapel Documentation 1.25 .

Today we have multiple variable declarations. The spec says:

var v1, v2, v3: t;

is translated in to

var v1: t; var v2: v1.type; var v3: v1.type;

we also have tuple variable declarations, e.g.

var (a, b) = (1, 2);

To what extent does the language allow combining these features?

It appears that, today, we can combine them as long as tuple declarations all have an initializer and a type. So this compiles:

var a, b=1, (c, d): (int, int);


but this does not:

var (a, b), (c, d): (int, int);


(it fails to compile with an error like error: use of 'tmp' before encountering its definition, type unknown).

Is this where we want to draw the line on the feature? Or, should

var (a, b), (c, d): (int, int);

translate into something equivalent to this:

var (a, b): (int, int), (c, d): (int, int);