regex - perl 解析格式错误的括号文本

Question

我将一串文本分成短语，每个短语用方括号括起来:

[pX textX/labelX] [pY textY/labelY] [pZ textZ/labelZ] [textA/labelA]

有时块不以 p 字符开头(如上面的最后一个)。

我的问题是我需要捕获每个块。这在正常情况下是可以的，但有时此输入格式错误，例如，某些块可能只有一个括号，或者没有。所以它可能看起来像这样:

 [pX textX/labelX] pY textY/labelY] textZ/labelZ

但它应该是这样的:

 [pX textX/labelX] [pY textY/labelY] [textZ/labelZ]

该问题不包括嵌套括号。在以前所未有的方式深入研究了大量不同人的正则表达式解决方案(我是正则表达式的新手)，并下载了备忘单并获得了正则表达式工具 (Expresso) 之后，我仍然不知道如何做到这一点。有任何想法吗？也许正则表达式不起作用。但是这个问题是如何解决的呢？我想这不是一个非常独特的问题。

编辑

下面是一个具体的例子:

$data= "[VP sysmH/VBD_MS3] [PP ll#/IN_DET Axryn/NNS_MP] ,/PUNC w#hm/CC_PRP_MP3] [NP AEDA'/NN] ,/PUNC [PP b#/IN m$Arkp/NN_FS] [NP >HyAnA/NN] ./PUNC";

这是来自@FailedDev 的一个很棒的紧凑型解决方案:

while ($data =~ m/(?:\[[^[]*?\]|[^[ ].*?\]|\[[^[ ]*)/g) { # matched text = $& }

但我认为需要补充两点来强调这个问题:

有些块根本没有括号

,/PUNC 和 w#hm/CC_PRP_MP3] 是需要分离的独立块。

但是，由于这种情况是固定的(即标点符号后跟右侧只有一个方括号的文本/标签模式)，我将其硬编码到解决方案中，如下所示:

my @stuff;
while ($data =~ m/(?:\[[^[]*?\]|[^[ ].*?\]|\[[^[ ]*)/g) {
    if($& =~ m/(^[\S]\/PUNC )(.*\])/) # match a "./PUNC" mark followed by a "phrase]"
    {
        @bits = split(/ /,$&); # split by space
        push(@stuff, $bits[0]); # just grab the first chunk before space, a PUNC
        push(@stuff, substr($&, 7)); # after that space is the other chunk
    }
    else { push(@stuff, $&); } 
}
foreach(@stuff){ print $_; }

尝试我在编辑中添加的示例，除了一个问题之外，这工作得很好。最后一个 ./PUNC 被遗漏了，所以输出是:

[VP sysmH/VBD_MS3]
[PP ll#/IN_DET Axryn/NNS_MP]
,/PUNC
w#hm/CC_PRP_MP3]
[NP AEDA'/NN]
,/PUNC
[PP b#/IN m/NN_FS]
[NP >HyAnA/NN]

我怎样才能保留最后一块？

Answer 1

你可以用这个

/(?:\[[^[]*?]|[^[ ].*?]|\[[^[ ]*)/

假设你的字符串是这样的:

[pX textX/labelX] pY textY/labelY]  pY textY/labelY]  pY textY/labelY]  [pY textY/labelY] [3940-823490-2 [30-94823049 [32904823498]

它不适用于例如: pY [[[textY/labelY]
Perl特定解决方案:

while ($subject =~ m/(?:\[[^[]*?\]|[^[ ].*?\]|\[[^[ ]*)/g) {
    # matched text = $&
}

更新 :

/(?:\[[^[]*?]|[^[ ].*?]|\[[^[ ]*|\s+[^[]+?(?:\s+|$))/

这适用于您更新的字符串，但如果需要，您应该修剪结果的空格。

更新:2

/(\[[^[]*?]|[^[ ].*?]|\[[^[ ]*|\s*[^[]+?(?:\s+|$))/

我建议打开一个不同的问题，因为你原来的问题与上一个完全不同。

"
(                 # Match the regular expression below and capture its match into backreference number 1
                     # Match either the regular expression below (attempting the next alternative only if this one fails)
      \[                # Match the character “[” literally
      [^[]              # Match any character that is NOT a “[”
         *?                # Between zero and unlimited times, as few times as possible, expanding as needed (lazy)
      ]                 # Match the character “]” literally
   |                 # Or match regular expression number 2 below (attempting the next alternative only if this one fails)
      [^[ ]             # Match a single character NOT present in the list “[ ”
      .                 # Match any single character that is not a line break character
         *?                # Between zero and unlimited times, as few times as possible, expanding as needed (lazy)
      ]                 # Match the character “]” literally
   |                 # Or match regular expression number 3 below (attempting the next alternative only if this one fails)
      \[                # Match the character “[” literally
      [^[ ]             # Match a single character NOT present in the list “[ ”
         *                 # Between zero and unlimited times, as many times as possible, giving back as needed (greedy)
   |                 # Or match regular expression number 4 below (the entire group fails if this one fails to match)
      \s                # Match a single character that is a “whitespace character” (spaces, tabs, line breaks, etc.)
         *                 # Between zero and unlimited times, as many times as possible, giving back as needed (greedy)
      [^[]              # Match any character that is NOT a “[”
         +?                # Between one and unlimited times, as few times as possible, expanding as needed (lazy)
      (?:               # Match the regular expression below
                           # Match either the regular expression below (attempting the next alternative only if this one fails)
            \s                # Match a single character that is a “whitespace character” (spaces, tabs, line breaks, etc.)
               +                 # Between one and unlimited times, as many times as possible, giving back as needed (greedy)
         |                 # Or match regular expression number 2 below (the entire group fails if this one fails to match)
            $                 # Assert position at the end of the string (or before the line break at the end of the string, if any)
      )
)
"