anchor.diff:                (lambda (needle hole)
                   (append1 hole needle))))
   
  +(defmacro nest (&rest things)
  +  "Like ~>>, but backward.
  +
  +This is useful when layering `with-x' macros where the order is not
  +important, and extra indentation would be misleading.
  +
  +For example:
  +
  +    (nest
  +     (with-open-file (in file1 :direction input))
  +     (with-open-file (in file2 :direction output))
  +     ...)
  +
  +Is equivalent to:
  +
  +    (with-open-file (in file1 :direction input)
  +      (with-open-file (in file2 :direction output)
  +        ...))
  +
  +This is useful when you would otherwise have to explicitly nest layers
  +of `with-x' forms:
  +
  +From UIOP, based on a suggestion by Marco Baringer."
  +  (reduce (lambda (outer inner)
  +            `(,@outer ,inner))
  +          things
  +          :from-end t))
  +
   (defmacro select (keyform &body clauses)
     "Like `case', but with evaluated keys.
   
  
positive.code: (in-package :serapeum)
  (in-readtable :fare-quasiquote)
  
  (import 'uiop:nest)
  
  (export '(eval-and-compile
            no nor nand
  
negative.code:           ensure ensure2
            ~> ~>>
            cond-every
            nest))
  
  (defmacro prog0 (&body body)
    "Execute BODY like `progn' but return nothing."
  