10_pipe.nula

// 10_pipe.nula - Pipe operator for data transformation
// Demonstrates: |> chaining with named functions and closures,
//               composing transformations, string processing
//
// Run: nulang examples/10_pipe.nula

// Pipeline stages as named functions
let double = fn(n) { n * 2 }
let add_ten = fn(n) { n + 10 }
let square = fn(n) { n * n }
let is_even = fn(n) { n % 2 == 0 }

// Arithmetic pipeline
let result = 5
    |> double
    |> add_ten
    |> double
perform IO.print("5 |> double |> +10 |> double = " + perform Int.to_string(result))

// Longer pipeline
let result2 = 3
    |> square
    |> add_ten
    |> double
    |> square
perform IO.print("3 |> sq |> +10 |> double |> sq = " + perform Int.to_string(result2))

// Boolean pipeline
let flag = 42 |> double |> is_even
perform IO.print("42 |> double |> even = " + perform Int.to_string(if flag then 1 else 0))

// String processing pipeline
let shout = fn(s) { s + "!" }
let greet = fn(name) { "Hello, " + name }

let message = "Nulang"
    |> greet
    |> shout
perform IO.print(message)

// Anonymous closures in a pipeline
let v = 41 |> fn(n) { n + 1 }
perform IO.print("41 |> inc = " + perform Int.to_string(v))

// Multi-step with closures
let w = 2
    |> fn(n) { n * 3 }
    |> fn(n) { n * n }
perform IO.print("2 |> *3 |> sq = " + perform Int.to_string(w))

// Pipeline that converts and formats
let output = 42
    |> double
    |> fn(n) { perform Int.to_string(n) }
    |> fn(s) { "Result: " + s }
perform IO.print(output)