How do you sort an array of objects?

Question

I have an object as follows:

[{:id=>2, :fname=>"Ron", :lname=>"XXXXX", :photo=>"XXX"}, {:id=>3, :fname=>"Dain", :lname=>"XXXX", :photo=>"XXXXXXX"}, {:id=>1, :fname=>"Bob", :lname=>"XXXXXX", :photo=>"XXXX"}] 

I want to sort this by fname, alphabetically case insensitive so it would result in

id: 1,3,2

How can I sort this? I'm trying:

@people.sort! { |x,y| y[:fname] <=> x[:fname] }

But that has no effect.

Answer 1

You can use sort_by.

@people.sort_by! { |x| x[:fname].downcase }

(the downcase is for the case insensitivity)

For completeness, the issues with the provided code are:

• the arguments are in the wrong order
• downcase is not being called

The following code works using the sort method.

@people.sort! { |x,y| x[:fname].downcase <=> y[:fname].downcase }

As proof that both of these methods do the same thing:

@people.sort_by {|x| x[:fname].downcase} == @people.sort { |x,y| x[:fname].downcase <=> y[:fname].downcase }

Returns true.