- Lexer: Generates a stream of tokens representing the lexical parts of the Swift input. The lexer uses a state object to store the token stream and other relevant information related to the Swift input. It is organized into three main files:

- ```lexer.js``` iterates over the Swift code, separating it into individual parts to be evaluated based on their precedence in Swift.

- ```parser.js``` is where the different modules come together to build the final tree output.

- ```rearrange``` are a group of functions that take the original tokens from the lexer and rearrange them in a manner that is conducive to building the AST so that it produces the equivalent JavaScript output of the Swift input.