Iterators vs Seq Semantics misundertanding

[mrsipan]

Hi everyone,

I am new to this language and I cannot get why this doesn't work for squint:

(ns day3
  (:require [squint.string :as squint.string]))
  ; (:require [clojure.string]))

(warn-on-lazy-reusage!)

(def data-raw
  "987654321111111
   811111111111119
   234234234234278
   818181911112111")

(defn -combine [v-of-digits]

  (for [el-of-v (range (count v-of-digits))
        el-of-v-sub (range (inc el-of-v) (count v-of-digits))]

   [(v-of-digits el-of-v) (v-of-digits el-of-v-sub)]
    ))

(defn digits->int
  [digits]
  (reduce (fn [acc el] (+ (* acc 10) el)) 0 digits))

(def joltage-total
  (->> (squint.string/split-lines data-raw)
       (map #(squint.string/trim %))
  ; (->> (clojure.string/split-lines data-raw)
  ;      (map #(clojure.string/trim %))
       (map #(mapv (comp parse-long str) %))
       (map (comp #(apply max %) -combine))
       (map digits->int)
       (apply +)
       ))


(println joltage-total)

where as it works as expected in clj/cljs.

Getting:

yield [v_of_digits(el_of_v2), v_of_digits(el_of_v_sub4)];
       ^

TypeError: v_of_digits is not a function

[borkdude]

@mrsipan Hey, welcome.

The issue is that you are passing an array as function. In CLJS these are vectors and usable as functions but in squint they aren't. So you can use (get v-of-digits el-of-v) instead.

https://squint-cljs.github.io/squint/?src=gzip%3AH4sIAAAAAAAAE3VS207jMBB9z1ccQEg2yEBbFlqQ%2BiNRHoZkGrly7GA7Zbtfj0wgOGVx8pI5l8kcj7ABDR1XBSCePL8O2jPK8DpoG29C9Nq2eKKAWaWSsgCec0Vt3H7wnBEK8UbeKmeVoX9H5XkI1PJZAhreoaFIytNbAZxv1o8Pf%2B5Xy8V4CgDrRX42qbRc3X%2B%2Fj%2BuRlZ5NoiTx%2Bae5hapd96Itozwot1ONbnUMVRpyH25rZ4MzfGNciwyWRcJ3zqNkk8oHCE%2B2ZYjaDTbOuCmA8XxyVRheJr629Vdd%2FlddpV4oRcszIBP9gqQ2svpoLqdpR4raahsLoMym9dwMNUPsLEqq009VENcQV0hfizsJNlLiDtNY4%2B3snYnUsooukklGaruFmC3BbeiNjspoy2G6zSkW0VGPixNF9LrD5dfyfFjO9%2BZXz%2BeZ64kos81ZHfWHFH7XoycfWBlnW4To5Q%2FyyLoQ1PfmiI7%2B4lJOO3TCzcL%2BBkbh9VRIQRai99pGY%2Bdpynd9l4JucwMAAA%3D%3D

[borkdude]

@mrsipan This program has one more weirdness. It relies on this to work:

(max [1 2] [1 3])

which I think is undefined behavior in Clojure. Consider the JVM counterpart:

user=> (max [1 2] [1 3])
Execution error (ClassCastException) at user/eval1 (REPL:1).
class clojure.lang.PersistentVector cannot be cast to class java.lang.Number (clojure.lang.PersistentVector is in unnamed module of loader 'app'; java.lang.Number is in module java.base of loader 'bootstrap')

[borkdude]

@mrsipan Here's the fixed version.

https://squint-cljs.github.io/squint/?src=gzip%3AH4sIAAAAAAAAE32S3W7bMAyF7%2F0UZw06SCu0NUl%2FkhbIHsQwBtWmDRWy5Eqy2%2BzpB0W2Zw%2FbaF8I5McjkiIzHpU87zNg84M9OXrrlSPk%2Fq1XJnz1wSnT4El6rDwFz4AFXmr72jta8SPIs4y9S2eENULLn2fhqPeyoU8xUFGNSgYpnHzPgKvj4fHh%2Fm6%2F2ybLABy2SztG125%2F9%2Ft%2FPCQqfseIxOSrUdxAlLZ9UYaQD8LWolKNCr6I1dfWIScdvQOYk6YhsNL2JmCB8thpspEVvn%2BZeWXKyc%2F%2Fml1kl%2FycNbSKLLL%2BEYn38OKSzed2EiJOyoQMyBftOKr6ksBqg1yWsapirjwauwH7ghjZ3nKQ5hy3mHsc5Vv5IQYqkQ9UbjFQubtoqxqss%2F577LDtpCPMcc6X51nnLFr5gfxz9K%2Fqm26I%2FonHq9VBNiSCDVJHWJxOYGmDvvlOqyC0MuTnXUmPwlrZYTNxwakW1%2BN7PY8a68X8j9bzOKUk%2BUfaSnpEWtkNaR7opPMktDVN3Hq%2BJhOyYbLr9HkazDWfF3PJLl539KasGz6vwWpUvwAeEUZUvgMAAA%3D%3D

[borkdude]

Not a bug, it just happens to work by accident in CLJS. max is only defined for numbers.

[borkdude]

you could do this to do it the correct way:

(if (pos? (compare vec1 vec2)) vec1 vec2)

[mrsipan]

Thanks a lot!, I do appreciate your work and time very much.