Control Flow

Rune uses conditional structures to control execution flow.

Conditionals: if / otherwise

Rune uses if and otherwise (instead of else or else if) to construct conditional branches. Parentheses around the conditions are optional and braces {} are required.

if score > 90 {
    write("Excellent!")
} otherwise {
    write("Keep practicing!")
}

Else-If Chains

You can chain multiple checks using otherwise condition:

if temperature > 30 {
    write("Hot")
} otherwise temperature > 15 {
    write("Warm")
} otherwise {
    write("Cold")
}

Truthiness

Conditions are evaluated for their truthiness. The following values are considered falsy in Rune:

• empty
• no (boolean false)
• 0 (the number zero)
• "" (empty word string)

Everything else is truthy, including non-empty words (like "no"), non-zero numbers, and yes.