ruby convert array into function arguments

ruby arrays function arguments
user1134991 picture user1134991 · Feb 19, 2013 · Viewed 40.8k times · Source

Say I have an array. I wish to pass the array to a function. The function, however, expects two arguments. Is there a way to on the fly convert the array into 2 arguments? For example:

a = [0,1,2,3,4]
b = [2,3]
a.slice(b)

Would yield an error in Ruby. I need to input a.slice(b[0],b[1]) I am looking for something more elegant, as in a.slice(foo.bar(b)) Thanks.

Answer

Johnsyweb picture Johnsyweb · Feb 19, 2013

You can turn an Array into an argument list with the * (or "splat") operator:

a = [0, 1, 2, 3, 4] # => [0, 1, 2, 3, 4]
b = [2, 3] # => [2, 3]
a.slice(*b) # => [2, 3, 4]

Reference:

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