Some useful coding stuff! Must review constantly...

Useful stuff!

ARRAYS---------------------------------------------------------------------------------------------

Q: How to easily create an array of strings?

  x = %w[a b c d]

Q: How to pull out items in an array and use that instead of the original array

  array.select!{ |x| x.prime? }

Q: Are .map and .collect the same thing?

  Basically.

HASHES---------------------------------------------------------------------------------------------

Q: How to turn an array into the keys of a hash?

  a = [1,2,3,4]
  b = %w[a b c d]
  x = a.zip(b)      #This is an intermediary to create an array of arrays
  h = Hash[x]

Q: How to turn an array into a pure hash?

  hash = Hash[*hash.flatten]

SUBLIME TEXT----------------------------------------------------------------------------------------

Q: How do I make the colours all ruby-friendly?

  Ctrl + Shift + "P"
  Type "ruby"
  Hit enter

TERMINAL-------------------------------------------------------------------------------------------

Q: How do I quickly get to the folder of the file I'm working on?

  Drag the file from finder directly into the terminal

GENERAL---------------------------------------------------------------------------------------------

Q: What's a one-line way of writing boolean if-else statements?

  boolean ? true : false

Q: What's a quick way to identify an empty method?

  def happy; end

Q: How can you make big numbers easier to read?

  1 million is the same as 1_000_000

Q: How can you chain something on separate lines?

  def square_times(array)
    array.find_all do |x|
      (2..x-1).select do |i|
        x % i == 0
        end.count == 0 
      end   
  end