Logical AND in Clojure

Question

Is Clojure's logical and different from the normal logical and (&&)? Why does this yield true

((and odd? #(> 10 %)) 6)

Doesn't and need 2 true statements to return true?

Answer 1

and doesn't necessarily return true. It actually returns false or nil if any of the given elements is false or nil. If none of them are, then it returns the very last element (it does not return true).

In your case the and returns the function #(> 10 %) (and nothing else) which is then applied to 6 which yields true. This is because both functions are neither nil nor false. This is how the steps would work:

((and odd? #(> 10 %)) 6)
(#(> 10 %) 6) 
;; => true

What you're looking for is to compose predicate functions:

((every-pred odd? #(> 10 %)) 6) ;; => false

FYI: There is also it's complement "or": some-fn.