Functions

Functions in Tea are declared with def. Parameters and return types are explicit, which keeps call sites easy to read and makes public APIs predictable.

Named functions

A named function declares its parameters up front, returns a value with return, and closes with end. This is the form you will use for most reusable program logic.

def add(a: Int, b: Int) -> Int
  return a + b
end

const total = add(1, 2)
@println(total)

Functions can also return early when a branch should stop execution immediately.

def describe(score: Int) -> String
  if score >= 90
    return "excellent"
  end

  return "keep going"
end

Lambdas and closures

Use lambdas for short pieces of behavior you want to pass around or return from another function. They use the |args| => expr form and can capture values from the surrounding scope.

def make_adder(base: Int) -> Func(Int) -> Int
  return |value: Int| => base + value
end

const add_two = make_adder(2)
@println(add_two(5))