Chapter 5

Exercise: Functions-1

list_concat = fn [a, b], [c, d] -> [a, b, c, d] end
[:a, :b, :c, :d] = list_concat.([:a, :b], [:c, :d])

sum = fn a, b, c -> a + b + c end
6 = sum.(1, 2, 3)

pair_tuple_to_list = fn {a, b} -> [a, b] end
[1234, 5678] = pair_tuple_to_list.({1234, 5678})

Exercise: Functions-2

fizzword = fn
  0, 0, _ -> "FizzBuzz"
  0, _, _ -> "Fizz"
  _, 0, _ -> "Buzz"
  _, _, n -> n
end

"FizzBuzz" = fizzword.(0, 0, 1)
"Fizz" = fizzword.(0, 1, 0)
"Buzz" = fizzword.(1, 0, 0)
0 = fizzword.(1, 1, 0)

Exercise: Functions-3

fizzbuzz = fn n -> fizzword.(rem(n, 3), rem(n, 5), n) end

"Buzz, 11, Fizz, 13, 14, FizzBuzz, 16" = Enum.map_join(10..16, ", ", fizzbuzz)

Exercise: Functions-4

prefix = fn prefix -> fn str -> "#{prefix} #{str}" end end

mrs = prefix.("Mrs")
"Mrs Smith" = mrs.("Smith")
"Elixir Rocks" = prefix.("Elixir").("Rocks")

Exercise: Functions-5

Enum.map([1, 2, 3, 4], &(&1 + 2))
Enum.each([1, 2, 3, 4], &IO.inspect/1)