LEVEL 4: ACTIVESUPPORT

gistfile1.rb

array.from(4)
array.to(2)
array.in_groups_of(3)
array.split(2)
array.index('word')

apocalypse = DateTime.new(2012, 12, 21, 14, 27, 45)
apocalypse.advance(years: 4, months: 3, weeks: 2, days: 1)
apocalypse.tomorrow
apocalypse.yesterday


options = {user: 'codeschool', lang: 'fr'}
new_options = {user: 'codeschool', lang: 'fr', password: 'dunno'}
options.diff(new_options) # {:password=>"dunno"}
options.stringify_keys    # {"user"=>"codeschool", "lang"=>"fr"}

defaults = {:lang => 'en', :country => 'us'}
options =  {:lang => 'fr', :user => 'codeschool'}
options.merge(defaults)         #=> {:user=>"codeschool", :lang=>"en", :country=>"us"}
options.reverse_merge(defaults) #=> {:user=>"codeschool", :lang=>"fr", :country=>"us"}



new_options = {user: 'codeschool', lang: 'fr', password: 'dunno'}
new_options.except(:password)               # {:user=>"codeschool", :lang=>"fr"}
new_options.assert_valid_keys(:user, :lang) # Unknown key(s): password (ArgumentError) throws an exception if the hash contains any keys besides those listed here