How to include a file with shadow-cljs/inline, but preprocess it first?

Question

Shadow-cljs has a resource loader that can include literal files into the Clojurescript code

(ns app.my
  (:require
   [shadow.resource :as rc]))

(rc/inline "file.txt")

I need a macro that includes the literal file, but preprocessed by some function. Let's for the sake of simplicity say that we uppercase the text of the file.

(ns app.my
  (:require
   [shadow.resource :as rc]))

(clojure.string/upper-case (rc/inline "file.txt"))

This code includes the regular text, and then uppercases it at run-time. I need it to be uppercased at macroexpansion, so that the uppercased text is included. Exactly like it would be if the original file was upper case.

I can't really fit this together, with macros expanding outside-in. Please help!

Thomas Heller · Accepted Answer · 2025-09-24 07:28:40Z

2

You can only do this by writing your own macro. inline itself is basically just using a helper function, which you can use in your own macro.

Basically as written in my macro guide you write 2 files.

First the simple CLJS file, which can contain additional code but must be at least this. So src/main/your/example.cljs (assuming src/main as the source path, adjust accordingly if not)

(ns your.example
  (:require-macros [your.example]))

Then the macro in src/main/your/example.clj

(ns your.example
  (:require
    [clojure.string :as str]
    [shadow.resource :as rc]
    ))

(defmacro my-inline [path]
  (-> (rc/slurp-resource &env path)
      (str/upper-case) ;; any post processing you want
      ))

And then whereever it is used (:require [your.example :as x]) and (x/my-inline "foo.txt").

answered Sep 24 at 7:28

Thomas Heller

4,5461 gold badge11 silver badges9 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

user2649762 Sep 25 at 7:04

That works. I was trying to implement it by wrapping the inline macro, but with the evaluation being outside-in, this didn't work. On a purely theoretical level, as me trying to grok macros, is it possible to make it by wrapping the inline macro with my own macro? (let's assume the library doesn't give me access to slurp-resource) This seems like something that should be possible to fully evaluate at macroexpand time, by expanding the inner inline macro first, turning the argument into a literal string, and then expanding the outer macro.

Thomas Heller Sep 25 at 7:29

I suppose it is technically possible, but not something I have ever done. Technically speaking macros are just functions, so anything is possible.

Collectives™ on Stack Overflow

How to include a file with shadow-cljs/inline, but preprocess it first?

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related