common lisp 的宏 TIME

time.txt

语法
  time form => result*

参数和值
  form --- 一个 form
  results --- form 返回的 values 
  
描述
  time 在当前的环境(词法和动态变量)中对 form 进行求值.
  time 会把各种用时打印出来

代码
  * (time (+ 1 2))

  Evaluation took:
    0.000 seconds of real time
    0.000002 seconds of total run time (0.000001 user, 0.000001 system)
    100.00% CPU
    504 processor cycles
    0 bytes consed

  3