Ruby Similar Constructs

and_different.rb

x = true and false
puts x # print out true

x = true && false
puts x # print out false

and_render.rb

render(:page) and return unless some_data.present?

and_similar.rb

# Identical
if true and false; end
if true && false; end

# Identical
foo = bar or raise "exception"
foo = bar || raise "exception"

block1.rb

# Equivalent to puts( (1..10).map { |i| i*2 } )
puts (1..10).map { |i| i*2 }

# Equivalent to puts( (1..10).map ) { |i| i*2 }
> puts (1..10).map do |i| i*2 end

block_scope.rb

class SomeModel < ActiveRecord::Base
  scope :for_user, lambda do |user_id|
    # Some logic here
  end
end