Hi How would I achieve in Ruby what the following line does in Java?: private BufferedImage buf; I need a new BufferedImage, but I don''t want to initialize it yet. Thanks. Jennifer --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
On Apr 16, 5:22 pm, jlesleyball <jlesleyb...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> Hi > > How would I achieve in Ruby what the following line does in Java?: > > private BufferedImage buf; > > I need a new BufferedImage, but I don''t want to initialize it yet. >You don''t need to declare things in advance in ruby, and typing is done dynamically so the ruby equivalent of that statement is basically an empty line :-) Fred --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe@googlegroups.com For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Hi Fred Thanks for answering my question again. I wanted to make it a method variable because I wanted to initialize it within the scope of a conditional loop as well as use it later on in the action method. So ,that''s why I thought I should declare it in the scope of the method. Is there something else I should be doing? JB On Apr 16, 1:20 pm, Frederick Cheung <frederick.che...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> On Apr 16, 5:22 pm, jlesleyball <jlesleyb...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> Hi > > > How would I achieve in Ruby what the following line does in Java?: > > > private BufferedImage buf; > > > I need a new BufferedImage, but I don''t want to initialize it yet. > > You don''t need to declare things in advance in ruby, and typing is > done dynamically so the ruby equivalent of that statement is basically > an empty line :-) > > Fred--~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Attributes of a class are private by default. You have to use attr acessor ang getter to get access to them. Http://www.rubyplus.org Free Ruby & Rails screencasts On Apr 16, 2008, at 1:20 PM, Frederick Cheung <frederick.cheung-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org > wrote:> > > > On Apr 16, 5:22 pm, jlesleyball <jlesleyb...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: >> Hi >> >> How would I achieve in Ruby what the following line does in Java?: >> >> private BufferedImage buf; >> >> I need a new BufferedImage, but I don''t want to initialize it yet. >> > You don''t need to declare things in advance in ruby, and typing is > done dynamically so the ruby equivalent of that statement is basically > an empty line :-) > > Fred > >--~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
On Apr 16, 10:45 pm, jlesleyball <jlesleyb...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> Hi Fred > > Thanks for answering my question again. I wanted to make it a method > variable because I wanted to initialize it within the scope of a > conditional loop as well as use it later on in the action method. > So ,that''s why I thought I should declare it in the scope of the > method. Is there something else I should be doing? >You don''t need to declare variables in advance in ruby like you do in java (1 exception: if you create a variable inside a block it won''t be visible outside the block unless it already existed). If you really must buf = nil is all you need. Fred --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe@googlegroups.com For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Yea one of the great parts about ruby is how its dynamically typed. If you want to declare a private variable accessible throughout the class use an instance variable: @buf = BufferedImage.new or in a local scope (not accessible outside the class): buf = ... if you use an instance variable and want to access it outside the class (public interface): attr_accessor :buf that automatically creates "getter" and "setter" for @buf which look like: def buf @buf end def buf=(value) @buf=value end -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Hi -- On Wed, 16 Apr 2008, Bcp wrote:> > Attributes of a class are private by default. You have to use attr > acessor ang getter to get access to them.Or, to put it slightly differently: An object''s instance variables are only visible to that object (i.e., only visible when ''self'' is that object). If you expose an instance variable through getter and/or setter methods, then you''ve given your object an "attribute", though there''s no real distinction between getter/setter methods that are implemented as simple wrappers around instance variables and those that aren''t. So instance variables are not, themselves, attributes; they''re just instance variables, and they can (but do not have to) participate in the creation of attributes. And there''s no language-level difference between an "attribute" and a getter and/or setter method in general (whether it uses instance variables or not). David -- Rails training from David A. Black and Ruby Power and Light: ADVANCING WITH RAILS April 14-17 New York City INTRO TO RAILS June 9-12 Berlin ADVANCING WITH RAILS June 16-19 Berlin See http://www.rubypal.com for details and updates! --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---