This is a simple example of a babel-plugin-macros macro.
You'll notice that
the code.js file
is importing
the greeting.macro.js file.
Then the imported identifiers are used throughout the code. The macro itself
is about as simple as you can get with a babel-plugin-macros macro. It accepts the
references to those imports and replaces the references with string literals.
Take a look at
the output.js file
to see what the result is. Now mess around
with it a bit to see what you can do with this thing!
Hopefully this helps you get started trying out writing a macro!
Writing a macro is similar to writing a babel-plugin except you give up a little power in favor of a simpler setup for you and the user of your macro (maybe also you). Because it's so similar to writing a babel plugin, it could be really helpful to learn how to write babel plugins and using ASTs. Here are some resources for that:
- babel-plugin-handbook
- Writing custom Babel and ESLint plugins with ASTs
- Code Transformation and Linting with Abstract Syntax Trees
From there, you may also want to reference the babel-plugin-macros docs
Good luck!