From: Ezra Zygmuntowicz <ezmobius@...>
Date: 2006-10-19T09:54:03+09:00
Subject: Re: whats this lambda code doing?


On Oct 18, 2006, at 5:48 PM, hemant wrote:

> I came across following code in typo's application.rb and I can't
> understand the last part,
>
>
>  def with_blog_scoped_classes(klasses=[Content, Article, Comment,
> Page, Trackback], &block)
>    default_id = this_blog.id
>    scope_hash = { :find => { :conditions => "blog_id = # 
> {default_id}"},
>                   :create => { :blog_id => default_id } }
>    klasses.inject(block) do |blk, klass|
>      lambda { klass.with_scope(scope_hash, &blk) }
>    end.call
>  end
>
> Method will be called with a block and will probably add some scope to
> the respective methods of ActiveRecord classes. But whats the last
> part?
> I mean, end.call?


    klasses.inject(block) do |blk, klass|
      lambda { klass.with_scope(scope_hash, &blk) }
    end.call

That outer block that ends on end returns the lambda made inside of  
that block. So end.call ends up being  lambda { klass.with_scope 
(scope_hash, &blk) }.call




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