RubyUnderscore

Closures are very useful tools, and ruby Enumerable mixin makes them even more useful.

However, as you decompose more and more your iterations into a sequence of maps, selects, rejects, group_bys and reduces, more commonly you see simple blocks such as:

collection.map { |x| x.invoke }
dates.select { |d| d.greater_than(old_date) }
classes.reject { |c| c.subclasses.include?(Array) }

RubyUnderscore modify classes so that you can also use a short notation for simple closures. With such, the above examples can be written as:

collection.map _.invoke
dates.select _.greater_than old_date
classes.reject _.subclasses.include? Array

Just replace the iterating argument with the underscore symbol (_), and ditch the parenthesis. More info

Quick Example

The example consists of getting all instance methods of String, Array, Class that end with 'd?'

require 'ruby_underscore'

class MethodFinder
  include RubyUnderscore::Base

  def find_interrogation_methods
    [String, Array, Class].map(_.public_instance_methods.grep /d\?$/).flatten.sort.uniq
  end
end
p MethodFinder.new.find_interrogation_methods

Using Ruby Underscore

As in the example above, simply by including the module include RubyUnderscore::Base on the class, all methods (class methods as well) will allow you to use the underscore symbol to write simple blocks.

RubyUnderscore

Quick Example

Using Ruby Underscore

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