Ruby: new array from one value in an array of objects

Question

Forgive me if this has already been asked, I couldn't find it.

I have an array of objects, like:

[<#Folder id:1, name:'Foo', display_order: 1>,
<#Folder id:1, name:'Bar', display_order: 2>,
<#Folder id:1, name:'Baz', display_order: 3>]

I'd like to convert that array into an array just of the names, like:

['Foo','Bar','Baz']

and, while I'm at it it would be nice if I could use the same technique down the road to create an array from two of the parameters, ie name and display order would look like:

[['Foo',1],['Bar',2],['Baz',3]]

What's the best 'Ruby Way' to do this kind of thing?

Thanks!

Answer 1

How about these?

# ['Foo','Bar','Baz']
array = folders.map { |f| f.name }
# This does the same, but only works on Rails or Ruby 1.8.7 and above.
array = folders.map(&:name)

# [['Foo',1],['Bar',2],['Baz',3]]
array = folders.map { |f| [f.name, f.display_order] }

Answer 2

How about:

a.collect {|f| f.name}