Rebol/Red Parse html规则返回true，但未插入任何内容 [英] Rebol / Red Parse html rules returns true but nothing is inserted

问题描述

我有一个解析规则，该规则返回true，但未按预期插入文本:html不变，而应在主结束div的末尾插入.我试图使用类似>如何使用REBOL解析HTML标记的计数器?

I have a parse rules that returns true but it doesn't insert my text as expected : the html is unchanged whereas it should have inserted at the end of the main closing div. I tried to use a counter like How to parse inside HTML tags with REBOL?

更新:我也不知道如何在counter = 0时立即退出解析，以免在main之后的最后一个div之前插入文本.

Update: I also don't know how to break out of the parsing as soon as counter = 0 so as not to insert text before last closing div after main.

    content: {<div class="main">
      <h1>
        Big TITLE
      </h1>
      <div>
        <section>
          <p>a paragraph</p>
        </section>
         <section>
          <p>a paragraph</p>
        </section>
          <section>
          <p>a paragraph</p>
        </section>
       </div>
       <div>
          <p>Blah Blah</p>
       </div>

    </div>
    <div>
      Another Div
    </div>
    }

    rules: [
      thru <div class="main">
      (div-count: 1)
      some [
        to "<div" (++ div-count) thru "<div" thru ">"
        |
        to </div> mark: (-- div-count if div-count = 0 [insert mark "closing main div"]) thru </div>
      ]
      to end 
    ]
    parse content rules

推荐答案

以下是使用探针进行调试的解决方案

Here a solution with probe to debug

rules: [
     thru <div class="main">
     (div-count: 1)
      some [
        "<div" (probe ++ div-count) skip
      |
        "</div>" mark:  ( probe -- div-count   if div-count = 0 [insert mark "closing main div"]) skip 
      |  skip
     ]
  ]
parse/all content rules 

您的规则存在的问题是，永远不会或很少会减去div计数.解析指针会直接指向下一个打开的 div ，因为 to 始终是第一个满足的条件.

The problems with your rules are, that the div-count is never or seldom subtracted. The parse pointer goes straight to the next opening div as to is always the first fulfilled condition.

如果在成功情况后添加要结束，则可以突围或者更好地从解析中返回.如果不确定，请使用方括号将 [成功的子规则...分组]分组

You can break out or better return from parse if you add a to end after a successful condition. If you are unsure use brackets for grouping [ sucessful sub-rules ... to end ]

带有结束规则的示例

end-rule: [] ; or none
rules: [
    thru <div class="main">
    (div-count: 1)
    some [
        ["<div" (++ div-count) skip]
    |
        ["</div>"mark:  (-- div-count   if div-count = 0 [insert mark "closing main div"  end-rule: [to end]]) end-rule ]
    |  skip
]

]

这篇关于Rebol/Red Parse html规则返回true，但未插入任何内容的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！