Array.pairs

Stream: Is there code for X?

[Adam Topaz]

Do we have something similar to the following?

def Array.pairs {α β : Type} (A : Array α) (B : Array β) : Array (α × β) := Id.run do
  let mut out := #[]
  for a in A do for b in B do
    out := out.push (a,b)
  return out

[Matthew Ballard]

docs#Array.zip ?

[Adam Topaz]

It's not quite zip.

[Matthew Ballard]

Ah ok.

[Adam Topaz]

#eval #[1,2,3].zip #[5,6,7]
-- #[(1, 5), (2, 6), (3, 7)]
#eval #[1,2,3].pairs #[5,6,7]
-- #[(1, 5), (1, 6), (1, 7), (2, 5), (2, 6), (2, 7), (3, 5), (3, 6), (3, 7)]

[Floris van Doorn]

docs#List.product

[Adam Topaz]

Yes, that's the one, but I would like it for arrays

[Floris van Doorn]

:face_palm: I should read

[Adam Topaz]

Although your response shows that I should name it Array.product :)

[Floris van Doorn]

Yeah, and I don't think it exists already.