The Flick Programming Language

We wrote Flick to explore compiler design. Keep reading to learn how our compiler works, or try writing Flick code in our sandbox.

Table of Contents

• How the compiler works
  • An overview of Flick
  • Step 1: Lexing/tokenization
  • Step 2: Parsing
  • Step 3: Compilation
• Installing the compiler
• Using the compiler

How the compiler works

An overview of Flick

Flick's syntax is based on Rust syntax. Here's a simple program:

pub fn main() {
    i64 i = 0
    while i < 10 {
        print(i)
        i += 1
    }
}

You can find other sample programs in the examples/ folder.

Step 1: Lexing/tokenization

Key question: how do we go from source code to tokens?

Step 2: Parsing

Key question: how do we go from tokens to an abstract syntax tree?

Step 3: Compilation

Key question: how do we go from an abstract syntax tree to LLVM code?

Installing the compiler

Assuming Rust is installed, you can install the Flick compiler with

cargo install --git "https://github.com/flick-lang/flick.git"

Before that, though, you will also need to install LLVM 18.1. For example, you could use brew:

brew install llvm@18

You will also need to tell llvm-sys where LLVM is located by adding the following line to ~/.zshrc (or an equivalent). First, run brew info llvm to figure out what the version number is. Then, run

export LLVM_SYS_181_PREFIX=$(brew --prefix llvm@18)

(Note: you should replace 181 in the environment variable with whatever version of LLVM is installed; 17.2, for example, corresponds to the environment variables LLVM_SYS_172_PREFIX.)

Using the compiler

You can compile Flick programs with flick <SOURCE_PATH>. For example,

flick examples/factorial.fl