Ruby or Rails array iteration syntax

Question

I came across a way in which a program extracted the name property of an object and found the syntax a little peculiar. This is dealing with the results of JSON response.

Our JSON response would be the following =

[{"id"=>9, "name"=>"Baked Potato w/ Cheese", "instructions"=>nil}, 
{"id"=>12, "name"=>"Baked Brussel Sprouts", "instructions"=>nil}]

results = JSON.parse(response.body)

def extract_name
  ->(object) { object["name"] }
end

results.map(&extract_name)

So I understand that results.map(&extract_name) returns the name of the JSON objects, I just don't understand how.

I'm unfamiliar with the ->(object) { object["name"] } syntax. Are there are other shorthand ways of doing this that may help me get a better idea of this type of syntax?

Answer 1

The arrow -> is a short syntax to create lambas. See " What do you call the -> operator in Ruby? ".

An alternative way could be the following snippet:

results.map { |object| object["name"] }