Here's a stupid example of what I mean by shadowing: user=> (defn foo [seq] #_=> (every? seq seq)) #'user/foo user=> (foo ["1" [1] '(1) {:1

Here's a stupid example of what I mean by shadowing: user=> (defn foo [seq] #_=> (every? seq seq)) #'user/foo user=> (foo ["1" [1] '(1) {:1 1} #{1}]) Execution error (IllegalArgumentException) at user/foo (REPL:2). Key must be integer Note that in a CL with a "seq" function foo would look like: (defun foo (seq) (every #'seq seq)) So there would be no ambiguity.