Clojurians Log v2

how would I mutate a string in clojure, get the result, and then mutate the result in a loop?

i think this is doable with a reduce, but the syntax is a bit clumsy and think there may be a better way to do this

java.lang.Strings are immutable, so you aren't going to be mutating them

i mean mutate as in reassign

local bindings are also immutable

I would just use loop/recur to answer the question I think you asking

in an imperative language, I would use a for loop and reassign a variable:

var x = "hello world";
var arr = ["l", "o"];
for (y in arr) {
  x = x.replace(y, "")
}

what is the best way to do this same operation in clojure?

Oh, reduce, definitely

That for loop is a good over arr

A fold

(reduce #(.replace %1 %2 "") "hello world" ["l" "o"])

so like this then?

is there anything like reduce that has the function as the last argument? it becomes a bit difficult to read when the arguments provided are place after the functionality

Thanks. Not sure to see the plus side of using cljs here though. Will have to tinker a bit. Enough reading, coding time.

Use a thread last macro

Eg (->> 10 (range) (filter odd?) (map #(* 2 %)) (reduce +))

Hi. I need to write spec (for reitit route coercion, but maybe it didn't matter). The problem is - my parameter contains square brackets, like ...&page[p]=10... For simple type checking (symbol "page[p]") int? works just fine, but when I try to write a more complex rule using s/def I got errors about namespace. I need to check the type and make the parameter optional. For simple symbols (without those brackets) all work just as needed. i.e. That works (s/def ::level int?) (s/def ::page int?) ;no brackets (s/def ::query-params (s/keys :req-un [::level] :opt-un [::page])) That works but checks only the type inside route data {:get {:parameters {:query :level int? (symbol "page[p]" int?)}... That not (s/def ::level int?) (s/def (symbol "page[p]") int?) ; got error (s/def ::query-params (s/keys :req-un [::level] :opt-un [(symbol "page[p]")]))

s/def is a macro so it's not going to evaluate that form.

The error Assert failed: k must be namespaced keyword or resolvable symbol (c/and (ident? k) (namespace k)) occurs when I try to evaluate the spec in the repl, or when call the router

Yes, because s/def is a macro and it expects a qualified keyword or symbol -- not a list. Macros do not evaluate their arguments.