Clojurians Log v2

Should we have a clojure.core/deref pattern?

(m/match (atom {:visits 100}) 
  @{:visits ?visits}
  [:p "Visits: " ?visits])
;; => [:p "Visits: " 100]

m/app can do that right? Is it worth hanging onto @ for something custom?

so… syntax sugar for (m/pred #(satisfies? IDeref %) (m/app deref <thing>)) ???

pros: it seems useful and convenient 🙂 cons: are there risks in conflating evaluation time with matching? I can’t think of any concrete risks here.

any thoughts on what @ might otherwise mean?

Well for one thing, I might want to match the literal symbol clojure.core/deref. So maybe something funk would be bad

Yeah, something like that. I don’t know if there are any real cons apart from stealing clojure.core/deref.

Which actually might be a bad idea.

Some folks may not realize that @ and clojure.core/deref are the same thing.

Yeah… We have the same “problem” with ~ .

At the same time, parsing ~ in a macro form specially is an uncommon but useful technique.

I guess from a data perspective, one could argue that @ is not data, but FWIW I also think that the idea of promises/future things is not a Clojure only thing, and a pretty useful idea (laziness too).

Just as a data point of 1 I have no problem quoting colliding symbols! 🙂

The fact that the Clojure reader expands @ does add a curveball, in that @x === (clojure.core/deref x) but I don’t see any immediate inconsistencies

Oh well '@x means '(clojure.core/deref x) doesn’t it? So either the operator would have to be smart or you can’t quote them like that :thinking_face: that does seem tricky!

i.e. ('clojure.core/deref ?x) is how it should be treated, but that’s not what it is.

but really '@x doesn’t make any sense anyhow sorry for the noise here I’m just trying to wrap my head around it! 🙂

> Just as a data point of 1 I have no problem quoting colliding symbols! I agree. Thats what ' is there for.

'@x

'(clojure.core/deref x)

(quote (clojure.core/deref x))

So

(match '(clojure.core/deref toast) '@toast true) ;; => true

and

(me/match '(clojure.core/deref toast) @toast true) ;; => true