Control Flow

If / Else

if age >= 18 {
    io.println("Adult")
} else if age >= 13 {
    io.println("Teenager")
} else {
    io.println("Child")
}

Conditions don't require parentheses. Braces are always required.

For Loops

Iterating over ranges

for i in 0..5 {
    io.println(i)  // 0, 1, 2, 3, 4
}

for i in 0..=5 {
    io.println(i)  // 0, 1, 2, 3, 4, 5 (inclusive)
}

Iterating over lists

names = ["Alice", "Bob", "Charlie"]

for name in names {
    io.println(name)
}

for i, name in names {
    io.println("${i}: ${name}")
}

Iterating over maps

config = {"host": "localhost", "port": "8080"}

for key, value in config {
    io.println("${key} = ${value}")
}

While-style loops

count = 0
for count < 10 {
    count += 1
}

Infinite loops

for {
    msg = receive_message()
    if msg == "quit" {
        break
    }
    process(msg)
}

Match

Pattern matching with match — Haira's replacement for switch:

match status {
    "ok" => io.println("Success"),
    "error" => io.println("Failed"),
    _ => io.println("Unknown")
}

Multi-line match arms

match command {
    "start" => {
        initialize()
        run()
    },
    "stop" => {
        cleanup()
        shutdown()
    },
    _ => io.println("Unknown command")
}

See Pattern Matching for advanced patterns including or-patterns, range patterns, and guards.

Break and Continue

for i in 0..100 {
    if i % 2 == 0 {
        continue  // Skip even numbers
    }
    if i > 10 {
        break  // Stop at 10
    }
    io.println(i)
}