I find I tend to need intermediate variables. In Clojure that's in the form of let bindings, like cmp-result-1 and cmp-result-2 in the following function.

(defn str-cmp
    "Takes two strings and compares them. Returns the string if a match; and nil if not."
    [str-1 str-2 start-pos substr-len]

    (let [cmp-result-1 (subs str-1 start-pos substr-len)
          cmp-result-2 (subs str-2 start-pos substr-len)]
        (compare cmp-result-1 cmp-result-2))) 

I could re-write this function without them, but to me, the function's purpose looks clearer. I tend to do this quite in a bit in my main, and that is primarily for debugging purposes, so I can pass a variable to print out intermediate output.

Is this bad form, and, if so, why?

Thanks.