Regex - Transferring HTML to Markdown for ol tag

Question

I have been struggling with this regex for while. I'm trying to transfer some HTML to mark down.

I have this code:

`"<ol>
   <li>This is a new list</li>
   <ol>
       <li>Embedded List</li>
       <li>Embedded List</li>
   </ol>
 </ol>"`

I need to add 4 space to all the <li> that are within two <ol> So just the second to <li> elements need the 4 spaces.

The regex in pseudo code would be find all <li> preceded by "<ol> any characters and <ol>.

This is what I tried so far (?<=\"<ol>\r\n)(?<=[A-Za-z]<ol>\r\n)<li> but no luck. Is this even possible using regex?

Your html string is not valid. The first `li` is not closed. While it might be possible to use regex, a html parser will be more reliable. — Lorenz Meyer, Aug 13 '15 at 18:26
[Using regular expressions to parse HTML: why not?](https://stackoverflow.com/q/590747) — Siguza, Aug 13 '15 at 18:46
So what you are telling me is not to use regex for this case. — Joseph Stablin, Aug 13 '15 at 19:09
@WashingtonGuedes: If you think so, I posted it as an answer. — Wiktor Stribiżew, Aug 20 '15 at 12:28

score 1 · Answer 1 · answered Aug 20 '15 at 12:28

You can use

(<li[^<]*>)([^>]*<\/li>)(?=(?![\s\S]*?<ol[^<]*>)[\s\S]*?<\/ol>)

Replace with $1 $2. See demo

The regex matches

(<li[^<]*>) - matches and captures an opening li node
([^>]*<\/li>) - matches and captures li node contents and closing li node
(?=(?![\s\S]*?<ol[^<]*>)[\s\S]*?<\/ol>) - checks if there is any text and closing ol node, but no opening ol tag is before it.

DISCLAIMER: Regex is not meant to parse HTML, use a proper parser instead. The current regex is just to show that it can process the sample input you provided.

Regex - Transferring HTML to Markdown for ol tag

1 Answers1