Question

我有一个代码，如果从emacs内的slime提示执行运行没有错误。如果我从提示符开始sbcl，我收到错误：

* (ei:proc-file "BRAvESP000.log" "lixo")

debugger invoked on a SB-INT:STREAM-ENCODING-ERROR:
  :UTF-8 stream encoding error on
  #<SB-SYS:FD-STREAM for "file /Users/arademaker/work/IBM/scolapp/lixo"
    {10049E8FF3}>:

    the character with code 55357 cannot be encoded.

Type HELP for debugger help, or (SB-EXT:EXIT) to exit from SBCL.

restarts (invokable by number or by possibly-abbreviated name):
  0: [OUTPUT-NOTHING    ] Skip output of this character.
  1: [OUTPUT-REPLACEMENT] Output replacement string.
  2: [ABORT             ] Exit debugger, returning to top level.

(SB-IMPL::STREAM-ENCODING-ERROR-AND-HANDLE #<SB-SYS:FD-STREAM for "file /Users/arademaker/work/IBM/scolapp/lixo" {10049E8FF3}> 55357)
0]

在两种情况下，我都使用相同的sbcl 1.1.8和相同的机器Mac OS 10.8.4。任何的想法？

代码：

(defun proc-file (filein fileout &key (fn-convert #'identity))
  (with-open-file (fout fileout
                   :direction :output
                   :if-exists :supersede
                   :external-format :utf8)
    (with-open-file (fin filein :external-format :utf8)
      (loop for line = (read-line fin nil)
        while line
        do 
        (handler-case
        (let* ((line (ppcre:regex-replace "^.*{jsonTweet=" line "{\"jsonTweet\":"))
               (data (gethash "jsonTweet" (yason:parse line))))
          (yason:encode (funcall fn-convert (yason:parse data)) fout)
          (format fout "~%"))
          (end-of-file ()
        (format *standard-output* "Error[~a]: ~a~%" filein line)))))))

Answer 1

这几乎可以肯定是一个错误。 JSON要求如果转义非BMP字符，则通过代理对完成。这是一个简单的例子，U + 10000（可选择在json中转义为“\ ud800 \ udc00”;我使用babel作为babel的转换不那么严格）：

(map 'list #'char-code (yason:parse "\"\\ud800\\udc00\"")) 
  => (55296 56320)

unicode代码点55296（十进制）是代理项对的开始，除非作为UTF-16中的代理项对，否则不应出现。幸运的是，通过使用babel将字符串编码为UTF-16并再次返回，可以很容易地解决这个问题：

(babel:octets-to-string (babel:string-to-octets (yason:parse "\"\\ud800\\udc00\"") :encoding :utf-16le) :encoding :utf-16le)
  => ""

您应该可以通过更改此行来解决此问题：

(yason:encode (funcall fn-convert (yason:parse data)) fout)

使用转换为UTF-16并返回的中间字符串。

(write-sequence
 (babel:octets-to-string
  (babel:string-to-octets
   (with-output-to-string (outs)
    (yason:encode (funcall fn-convert (yason:parse data)) outs))
   :encoding :utf-16le)
  :encoding :utf-16le)
 fout)

我提交了一个已被接受的补丁，以便在yason中解决这个问题：

https://github.com/hanshuebner/yason/commit/4a9bdaae652b7ceea79984e0349a992a5458a0dc

sbcl编码错误只在从提示符执行时？

1 个答案: