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= Scope Builder

Build up named scopes conditionally.


== Install

First specify it in your Rails config.

	config.gem 'ryanb-scope-builder', :lib => 'scope_builder', :source => 'http://gems.github.com'

And then install it.

  rake gems:install

Rails 2.1 or later required.


== Usage

This gem adds the scope_builder method to all Active Record models. A 
builder behaves exactly like any other named scope except that calling 
other named scopes on it will alter the builder itself rather than 
returning a new named scope.

  builder = Product.scope_builder
  builder.released.visible # call a couple named scopes to change builder
  builder.cheap if only_show_cheap_products? # build scopes conditionally

The scope_builder method can also take a block which will return the 
builder. This is useful when you are using the builder in a model 
search method.

  # in product model
  def self.search(options)
    scope_builder do |builder|
      builder.released.visible
      builder.cheap if options[:cheap]
    end
  end

The scope_builder method can also be called on an existing scope.

  products = Product.released.visible
  builder = products.scope_builder
  builder.cheap if only_show_cheap_products?


== Development

This project can be found on github at the following URL.

http://github.com/ryanb/scope-builder/

If you would like to contribute to this project, please fork the 
repository and send me a pull request.