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Defining Functions

Defining functions involves using the fn keyword to create reusable code blocks that can be called later.

Why this exists​

Function definitions allow developers to organize code into logical units that can be invoked multiple times.

How it works​

Start with fn, followed by the function name, optional parameters in parentheses, and the function body in braces. The body can contain statements and optionally a return statement.

Examples​

Function without parameters:

fn say_hello() {
  print("Hello!")
}

Function with parameters:

fn add(a, b) {
  return a + b
}

Function with return:

fn square(x) {
  return x * x
}

Common mistakes​

  • Omitting the fn keyword.
  • Forgetting parentheses even for no parameters.
  • Not enclosing the body in braces.