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.
