anonymous.ex

square = fn(x) -> x * x end

# calling an anonymous function uses a period
# before the parentheses
4 = square.(2)


# pattern matching the arguments can be used
first = fn([head|rest]) -> head end
1 = first.([1, 2])

# anonymous functions are commonly used as arguments
# to other functions
[1, 4, 9] = Enum.map([1, 2, 3], square)
[3, 4, 5] = Enum.map([1, 2, 3], fn(x) -> x + 2 end)