anchor.diff:     ```cl
      (struct :foo bar)
      ```"
  -  (when (= (% (# entries) 1) 1)
  +  (when (= (% (# entries) 2) 1)
       (error "Expected an even number of arguments to struct" 2))
     (with (out (empty-struct))
       (for i 1 (# entries) 2
  
positive.code:    This is designed for performance critical code where you will create a lot of
     structures with the same format."
  
    (when (= (% (# entries) 1) 1)
      (error "Expected an even number of arguments to const-struct" 2))
    (let* [(name (gensym))
           (body `(lambda (,name)))]
  
negative.code:   "A variation of [[struct]], which will not perform any ocercing of the KEYS in entries.
  
     Note, if you know your values at compile time, it is more performant to use [[const-struct]]."
    (when (= (% (# entries) 2) 1)
      (error "Expected an even number of arguments to struct" 2))
    (with (out (empty-struct))
      (for i 1 (# entries) 2
  