;; It's too inconvenient to make `e' a constant because it's used as ;; a temporary variable all the time. (defvar e (exp 1) "The value of e (2.7182818...).")こんなのもあった。
;; provide an easy hook to tell if we are running with floats or not. ;; define pi and e via math-lib calls. (much less prone to killer typos.) (defconst pi (* 4 (atan 1)) "The value of Pi (3.1415926...).")知らなかったけど、pi って使ったことがあるようなかすかな記憶が。。。