I am playing around with the Selmer library (version 1.12.33) and have constructed a simple custom tag. I want to modify this tag further to allow the use of filters in a similar vein how some standard tags, e.g. if, for, script, and style seem to allow it.
Seems the documentation doesn't cover it; does anyone know how to do this?
Here is some (very simplified) example code distilling the essence:
(selmer.parser/add-tag! :hello
(fn [[arg & _] ctx] ; use only first argument
(let [[name & filters] (clojure.string/split arg #"\|")] ; separate arg1 from appended filter(s)
(format "Hi, %s!" (or ((keyword name) ctx) name))))) ; look up in context map, else use as-is
Obviously, I need to use filters here somehow, but I don't know how...
(def myctx {:greet/name "world"})
(selmer.parser/render "{{greet/name|upper|safe}}" myctx)
; SUCCESS: expected & actual: WORLD
(selmer.parser/render "{% hello greet/name|upper|safe %}" myctx)
; FAIL: Expected: Hi, WORLD!, actual: Hi, world!
I guess the erm, obvious way would be to co-opt Selmer to do its stuff on only the input arg, without trying to re-invent Selmer's wheel. The custom tag would then be something like:
(selmer.parser/add-tag! :hello
(fn [[arg & _] ctx] ; use only first argument
(let [name (selmer.parser/render (str "{{" arg "}}") ctx)]
(format "Hello, %s!" name))))
Too obvious? I would be grateful for a better answer or even comments regarding pitfalls with this method, as I am fairly new to Clojure and don't trust my own insight yet.