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Type Helpers

Built-in functions for checking value types.

Why this exists​

Dynamic typing requires runtime type checking for robust programs.

How it works​

Type helpers return boolean values indicating whether a value matches a specific type.

Examples​

fn processValue(value) {
  check isNumber(value) {
    return value * 2
  } else check isString(value) {
    return upper(value)
  } else check isArray(value) {
    return len(value)
  } else {
    throw "Unsupported type"
  }
}

# Also available: type() function
set typeName = type(42)  # "number"

Common mistakes​

  • Using type() for comparisons instead of type helpers
  • Not handling all possible types in functions