On Thursday, 19 February 2015 at 04:38:32 UTC, thedeemon wrote:
Creating tuples and returning them from functions is trivial in D:

auto getTuple() { return tuple("Bob", 42); }

but using them afterwards can be confusing and error prone

auto t = getTuple();
writeln("name is ", t[0], " age is ", t[1]);

I really missed the ML syntax to write

let (name, age) = getTuple();

Turns out this is ridiculously easy to implement in D, so here's my very tiny module for this:

https://bitbucket.org/infognition/dstuff/src (scroll down to letassign.d)

It allows you to write:

int x, y, z, age;
string name;

let (name, age) = getTuple();           // tuple
let (x,y,z) = argv[1..4].map!(to!int);  // lazy range
let (x,y,z) = [1,2,3];                  // array

SomeStruct s;
let (s.a, s.b) = tuple(3, "piggies");

If a range or array doesn't have enough elements, this thing will throw, and if it's not desired there's
let (x,y,z)[] = ...
variant that uses just the available data and keeps the rest variables unchanged.

That's pretty neat! May I turn this code into a d-idioms? Name and link will be kept of course.

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