03: Sourceror Basics

The Refactoring Cycle

The refactoring cycle has three steps:

1. Convert code to AST
2. Modify the AST
3. Convert AST to code

Elixir has many tools to modify deeply nested data structures, and any tool will work.
Example tools include Kernel.update_in and PhStTransform.

Sourceror provides a set of utility functions to transform the AST. We’ll start by looking at Sourceror.postwalk.

Sourceror Postwalk

Let’s start with a live example:

Mix.install([{:sourceror, "~> 0.5"}])
ast = "x = 2 + 4" |> Sourceror.parse_string!()
Sourceror.postwalk()

Other Sourceror Functions