Guess number / PragProg Elixir 1.6

chop.exs

defmodule Chop do
	def guess(n, range) do
		mid = middle_of range
		IO.puts("Is it #{mid}?")
		attempt n, middle_of(range), range
	end

	def attempt(n, guess, _range) when n == guess do
		IO.puts n
	end

	def attempt(n, guess, range) when n < guess do
		IO.puts("No, too high.")
		guess(n, lower_half_of range)
	end

	def attempt(n, guess, range) when n > guess do
		IO.puts "No, too low."
		guess n, higher_half_of range
	end

	def middle_of(range) do
		a..b = range
		a + div b - a, 2
	end

	def lower_half_of(range) do
		a.._b = range
		a..middle_of range
	end

	def higher_half_of(range) do
		_a..b = range
		middle_of(range)..b
	end
end

iex session

mt@MacBook-Pro-Timofej:~/Learning/pragelixir% iex
Erlang/OTP 20 [erts-9.3] [source] [64-bit] [smp:4:4] [ds:4:4:10] [async-threads:10] [hipe] [kernel-poll:false] [dtrace]

Interactive Elixir (1.6.4) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)> c "chop.exs"
[Chop]
iex(2)> Chop.guess(273, 1..1000)
Is it 500?
No, too high.
Is it 250?
No, too low.
Is it 375?
No, too high.
Is it 312?
No, too high.
Is it 281?
No, too high.
Is it 265?
No, too low.
Is it 273?
273
:ok
iex(3)>