Last active
June 22, 2019 00:20
-
-
Save alandipert/2346460 to your computer and use it in GitHub Desktop.
It's sweet that IFn is a protocol in ClojureScript
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| (extend-type js/RegExp | |
| cljs.core/IFn | |
| (-invoke ([this s] (re-matches this s)))) | |
| (#"foo.*" "foobar") ;=> "foobar" | |
| (#"zoo.*" "foobar") ;=> nil | |
| (filter #".*foo.*" ["foobar" "goobar" "foobaz"]) ;=> ("foobar" "foobaz") |
Nowadays, no longer need to hide seekrits. Keywords and symbols are actually types that support IFn:
https://github.com/clojure/clojurescript/blob/r1.7.228/src/main/cljs/cljs/core.cljs#L2941-L2945
https://github.com/clojure/clojurescript/blob/r1.7.228/src/main/cljs/cljs/core.cljs#L945-L949
@mfikes I can understand keywords, but why are symbols functions of collections? That seems like a juicy one to leave open for users.
Edit
Nevermind, answered my own question. Clojure does the same thing, which must have been the rationale. Fortunately regexes and many other atoms are available for IFn extension 😈
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
This Old Gist™
Despite the fact that this is seekrit I still point it out to clojure journeyfolk because I think it teaches deep Clojure by way of radical ClojureScript in one beautiful motion.