Getting Started (Olang Reference Manual 0.0.1)

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3 Getting Started ¶

Welcome to the O programming language! This chapter will introduce you to the basics of the language’s syntax. We’ll cover variables, data types, operators, control flow, and functions.

By the end of this chapter, you’ll have a solid foundation in the O language syntax and be ready to start writing your own programs. If you are already familiar with C-like languages, you will find out that O behave pretty much the same with some small quirks. Let’s dive in!

An olang program
Functions
Comments
Variables
Flow control
Primitive data types
Binary Operations
Pointers

3.1 An olang program ¶

An O programming language program starts with a main function. This function must return the program exit code.

fn main(): u8 {
  return 0
}

To compile the program you can use olc.

olc my_prog.ol -o my_prog
./my_prog

3.2 Functions ¶

Unlike C, O language does not require function prototypes. This means you can call a function before it’s defined, making your code more flexible and easier to read in many cases.

fn main(): u8 {
  return fib(8)
}

fn add(a: u32, b: u32): u32 {
  return a + b
}

fn fib(n: u32): u32 {
  if n <= 2 {
    return n
  }

  return add(fib(n - 1), fib(n - 2))
}

3.3 Comments ¶

Comments starts with a #.

# Hi I'm a comment and I'll be ignored by the compiler.

3.4 Variables ¶

var answer: u32 = 42

3.5 Flow control ¶

Any non zero expr is true.

If-Else
While loop

3.5.1 If-Else ¶

if expr {
  # statement
} else if expr {
  # statement
} else {
  # statement
}

While loop

while expr {
  # statement
}

3.5.2 While loop ¶

while expr {
  # statement
}

3.6 Primitive data types ¶

‘u8’: Unsigned 8 bits.
‘u16’: Unsigned 16 bits.
‘u32’: Unsigned 32 bits.
‘u64’: Unsigned 64 bits.