Question

I am trying to build a quick toc from an html content. (to make it short)

The code is dead simple:

(defn toc [content]
 (doseq [i (take 5 (iterate inc 1))] 
   (let [h  (str "h" i)]
    (println ($ content h)))))

where content is the html content, and $ is a macro required from clojure-soup

While

($ content "h1")

works, and returns a list of all the tags.

Simple:

($ content (str "h" 1))

just won’t make it whatever I do.

How do I force

(str "h" 1) 

to be properly eval-ed before the macro is called ?

Bonus points for explaining why 🙂

Answer 1

This is not possible if, as you imply, $ is a macro: it’s simply not how macros work. The macro needs to expand into something, at compile time, and it can only do so once. You have run-time data, like the various values of h, but there is no way to use that at compile-time. To me it sounds like $ should have been a function.