Enumeradical

A most amazing collection of useful functions filling common tasks when iterating over collections

What is this?

I love enumerable. I really do. I use the functions it provides with the utmost alacrity. Nothing makes me sadder than seeing a #each used to populate an array. Once you start using them a lot in production systems, you notice a bunch of common patterns.

How do I use it?

It is a gem, so just do

gem install enumeradical

then rock the house by requiring it. It sets itself up!

require 'enumeradical'

Why would I use it?

I have an array of objects, and I need to convert them to another type.

class MyNumberPresenter
  def initialize(number)
    @number = number
  end
end

[1,2,3].map { |number| MyNumberPresenter.new(number) }
# => [#<MyNumberPresenter:0x0000010086b9c8 @number=1>, #<MyNumberPresenter:0x0000010086b630 @number=2>,
      #<MyNumberPresenter:0x0000010086b540 @number=3>]

NO MORE! Use Enumerable#map_to(type)

class MyNumberPresenter
  def initialize(number)
    @number = number
  end
end

[1,2,3].map_to MyNumberPresenter
# => [#<MyNumberPresenter:0x0000010086b9c8 @number=1>, #<MyNumberPresenter:0x0000010086b630 @number=2>,
      #<MyNumberPresenter:0x0000010086b540 @number=3>]

I have an array of objects, and I want to map them to the value they give from indexing into another object.

require 'date'
[1,2,3].map { |index| Date::ABBR_DAYNAMES[index] } # => ["Mon", "Tue", "Wed"]

NO MORE! Use Enumerable#map_into

require 'date'
[1,2,3].map_into Date::ABBR_DAYNAMES # => ["Mon", "Tue", "Wed"]

I have an array of objects, and I'd like to convert them using a given object's method.

class Converter
  def hellos(times)
    "hello"*times
  end
end

converter = Converter.new

[1,2,3].map { |times| converter.hellos(times) }
# => ["hello", "hellohello", "hellohellohello"]

NO MORE! Use Object#map_over

class Converter
  def hellos(times)
    "hello"*times
  end
end

converter = Converter.new

converter.map_over [1,2,3], :hellos
# => ["hello", "hellohello", "hellohellohello"]

I have an array of objects, and I'd like to sort them based on another enumerable.

class Thingy
  def initialize(foo)
    self.foo = foo
  end
  attr_accessor :foo
end

thingies = [Thingy.new("abc"), Thingy.new("def"), Thingy.new("ghi")]
arry = ["def", "abc", "ghi"]

thingies.sort_like(arry, :foo)
# OR
thingies.sort_like(arry) { |t| t.foo }

Is this useful?

YES!!!!! Use it.

Who built this

Corey Haines and Ryan Briones

License

MIT. See LICENSE