This article is deprecated.I've marked this article as deprecated. It is either because the gem or plugin discussed in this article is no longer maintained, or I've changed my opinion on it. This article is here only as an historic reference.

Basic Named Scopes

Cal it tiny, I don't care. I've made a gem named BasicNamedScopes.

Basic Usage

I was fed up with writing:

Post.all(:conditions => { :published => true }, :select => :title, :include => :author)

So with BasicNamedScopes, you can now write:

Post.conditions(:published => true).select(:title).with(:author)

All named scopes are called the same, except for include, which is now called with, because include is a reserved method.

Reuse them by making class methods:

class Post < ActiveRecord::Base
  def self.published
    conditions(:published => true)
  end

  def self.visible
    conditions(:visible => true)
  end

  def self.index
    published.visible
  end
end

Also, the all-method is a named scope now, so you can chain after callling all, for greater flexibility.

Post.all.published

Arrays can be used as multple parameters too, sparing you some brackets.

Post.with(:author, :comments).conditions("name LIKE ?", query)

The read_only and lock scopes default to true, but can be adjusted.

Post.readonly         # => same as Post.all(:readonly => true)
Post.readonly(false)  # => same as Post.all(:readonly => false)

Why?

NamedScopes are really handy and they should play a more central theme in ActiveRecord. While I heard that Rails 3 will support similar syntax, there is no reason to wait any longer.

I find defining named scopes very ugly, especially when dealing with parameters. Just compare the amount of curly braces!

# Using normal named scope:
named_scope :name_like, lambda { |query| { :conditions => ["name LIKE ?", query] } }

# Using BasicNamedScopes
def self.name_like(query)
  conditions("name LIKE ?", query)
end

Also, regular named scopes don't support using other named scopes at all!

I found myself implementing these named scopes (mostly conditions, but others too) so often, that a little gem like this would be the obvious choice. Use it if a gem like searchlogic is overkill for your needs.

Installing

The gem is called "basic_named_scopes". You know how to install it.

gem install basic_named_scopes

Use it in Rails:

config.gem "basic_named_scopes"