Ruby: how to splice an array into a list Lisp-style?

Question

This is something I find myself wanting to do occasionally. Say I have a list of arguments. In Lisp, I can go like

`(imaginary-function ,@args)

in order to call the function with the array turned from one element into the right number of arguments.

Is there similar functionality in Ruby? Or am I just using a completely wrong idiom here?

In Lisp that's neither a function call, nor an array. It's just a list with another list spliced in. — Rainer Joswig, Aug 29 '12 at 21:29

David Grayson · Accepted Answer · 2012-08-29T15:57:26.680

9

Yes! It's called the splat operator.

a = [1, 44]
p(*a)

edited Aug 29 '12 at 15:57

answered Aug 29 '12 at 15:48

David Grayson

`puts(a)` and `puts(*a)` have the same output – Stefan Aug 29 '12 at 15:52
Yeah, not a great example. I'll change it to "p(*a)". – David Grayson Aug 29 '12 at 15:56
Perfect, this is exactly what I was looking for. Seems a little weird syntactically that you use the same operator to collect (*args) in a function, but it makes sense mnemonically I guess. – TG-T Aug 30 '12 at 00:15

score 3 · Answer 2 · answered Aug 29 '12 at 15:47

3

This is the splat operator: function(*list)

answered Aug 29 '12 at 15:47

dfb

2 Answers2