From: w_a_x_man <w_a_x_man@...>
Date: 2010-10-27T00:00:14+09:00
Subject: Re: embedded hash in array to selected-array

On Oct 26, 9:28 am, Josh Cheek <josh.ch...@gmail.com> wrote:
> On Tue, Oct 26, 2010 at 8:55 AM, Karácsony K. <kol...@gmail.com> wrote:
> > Hi!
>
> > I have this array:
> > users = [ { :id => 1, :name => 'Stephan'}, { :id => 2, :name =>
> > 'Carol'}, { :id => 3, :name => 'Lizi'} ]
>
> > How can i make a users_names, which will contain ['Stephan', 'Carol',
> > 'Lizi'] ?
> > Thanks:Koli
>
> > --
> > Posted viahttp://www.ruby-forum.com/.
>
> It seems you are using hashes to collect related data. If its just a quick
> one time use, a struct might be easier to work with. If you want something
> more robust, perhaps a class.
>
> User = Struct.new(:id ,:name)
> users = [ User.new(1,'Stephan') , User.new(2,'Carol') , User.new(3,'Lizi') ]
> users # => [#<struct User id=1, name="Stephan">, #<struct User id=2,
> name="Carol">, #<struct User id=3, name="Lizi">]
> users.map { |user| user.name } # => ["Stephan", "Carol", "Lizi"]
> users.map { |user| user.id   }   # => [1, 2, 3]

Or even:
users.map( &:name )
    ==>["Stephan", "Carol", "Lizi"]
VERSION
    ==>"1.8.7"