ITERATORS & BLOCKS

array_recap.rb

musicians = ['David Gilmour', 'Roger Waters', 'Richard Wright', 'Nick Mason']

puts musicians.length

# CRUD

# create
musicians << "Eminem"
puts musicians.length

#read
puts musicians[1]

#update
puts musicians[0] = "50cent"

#delete
musician.delete_at(2)
musician.delete("Roger Waters")

count.rb

musicians = [
  'David Gilmour',
  'Roger Waters',
  'Richard Wright',
  'Nick Mason'
]

counter = 0
musicians.each do |musician|
  if musician.start_with?("R")
    counter += 1
  end
end

# r_musicians = musicians.count do |musician|
#   # musician[0] == "R"
#   musician.start_with?("R")
# end

p r_musicians

each.rb

musicians = ['David Gilmour',
  'Roger Waters',
  'Richard Wright',
  'Nick Mason'
]

musicians.each do |musician|
  puts "- #{musician}"
end

musicians.each_with_index do |musician, index|
  puts "#{index + 1}. #{musician}"
end

map.rb

musicians = [
  'David Gilmour',
  'Roger Waters',
  'Richard Wright',
  'Nick Mason'
]

first_names = musicians.map do |musician|
  #'David Gilmour'.split => ["David", "Gilmour"]
  musician.split.first
end

p first_names

# upcased_musicians = musicians.map do |musician|
#   musician.upcase
# end


## Map behaviour using .EACH
# upcased_musicians = []
# musicians.each do |musician|
  #   upcased_musicians << musician.upcase
# end


# p musicians
# p upcased_musicians

range.rb

musicians = ['David Gilmour', 'Roger Waters', 'Richard Wright', 'Nick Mason']

range = (1..10)
puts (1...10).to_a

for index in (0...musicians.length)
  puts "- #{musicians[index]}"
end

select.rb

musicians = [
  'David Gilmour',
  'Roger Waters',
  'Richard Wright',
  'Nick Mason'
]

r_musicians = musicians.select do |musician|
  musician.start_with?("R")
end

p r_musicians

# .map    [] -> [] same size
# .count  [] -> Integer
# .select [] -> []

timer.rb

def timer
  start_time = Time.now

  yield # workload

  end_time = Time.now
  "Elapsed time: #{end_time - start_time}"
  puts "_________"
end

puts timer do
  puts "Task 1"
  sleep(2)
  puts "Task 1 Done"
end

puts timer do
  puts "Task 2"
  sleep(1)
  puts "Task 2 Done"
end

yield_with_params.rb

def greet(name)
  capitalized_name = "#{name.capitalize}"
  yield(capitalized_name)
end

j_greet = greet('john') do |name|
  "Hello, #{name}"
end

p_greet = greet('paul') do |name|
  "Ciao, #{name}"
end

puts j_greet
puts p_greet