Question

我正在从书中删除示例：ANSI Common Lisp，第14.6章条件。

sbcl没有以正确的顺序打印提示符：

示例代码：

(defun user-input (prompt)
    (format t prompt)
    (let ((str (read-line)))
      (or (ignore-errors (read-from-string str))
      nil)))

在sbcl测试中，提示不会按顺序打印：

* (defun user-input (prompt)
    (format t prompt)
    (let ((str (read-line)))
      (or (ignore-errors (read-from-string str))
      nil)))

STYLE-WARNING: redefining COMMON-LISP-USER::USER-INPUT in DEFUN

USER-INPUT
* (user-input "Please type an expression> ")
test
Please type an expression> 
TEST
* (user-input "Please type an expression> ")
#%@#+!!
Please type an expression> 
NIL
*

但是在clisp中，提示按顺序打印，并按预期工作：

[5]> (defun user-input (prompt)
    (format t prompt)
    (let ((str (read-line)))
      (or (ignore-errors (read-from-string str))
You are in the top-level Read-Eval-Print loop.
Help (abbreviated :h) = this list
Use the usual editing capabilities.
(quit) or (exit) leaves CLISP.
  nil)))
USER-INPUT
[6]> (user-input "Please type an expression> ")
Please type an expression> #%@#+!!
NIL
[7]>

Answer 1

之后插入force-output format user-input以避免i / o缓冲问题：force-output 通常情况下，在换行或换行之前，实际上没有任何内容打印到设备上 finish-output或<!DOCTYPE html> <html> <head> <title>highlight.js example</title> <link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/8.7/styles/darkula.min.css"> <script src="//cdnjs.cloudflare.com/ajax/libs/highlight.js/8.7/highlight.min.js"></script> <script> hljs.initHighlightingOnLoad(); </script> </head> <body> <pre><code class="markdown"> # hello world you can write text [with links](http://example.com) inline or [link references][1]. * one _thing_ has *em*phasis * two __things__ are **bold** [1]: http://example.com --- hello world =========== > markdown is so cool so are code segments 1. one thing (yeah!) 2. two thing `i can write code`, and `more` wipee! </code></pre> </body> </html>。

sbcl - 为什么不按顺序执行代码

1 个答案: