正则表达式，找到具有某些子节点的xml节点（在Sublime Text中）

Question

I am looking for the regular expression (for Sublime Text) to select xml elemets which have a certain sub-element. I can select all the elements with this:

(?s)<wp:comment>.+?</wp:comment>

This works perfect but I want to find the blocks which contain

<wp:comment_approved>0</wp:comment_approved> 

And not which contain:

<wp:comment_approved>1</wp:comment_approved>

So I need a lookaraound (look ahead or look behind) or conditional expression, but I cant get it right. When I try:

(?s)<wp:comment>.+?comment_approved>1.+?</wp:comment>   

It selects more elements in one select than it should.

It seems very simple but I cant find the right answer anywhere.

Answer 1

I suppose this would work:

(?s)<wp:comment>(?:(?!<wp:comment>).)+?+<wp:comment_approved>0.+?+</wp:comment>

Note the possessive matching ( .+?+ ) to avoid unnecessary backtracking.

Answer 2

Oke, the answer to the problem explained. Find only the comments which are not approved.

<xml>
    <node>bla</node>
    <wp:comment>
        <node>bla</node>
        <node>bli</node>
        <wp:comment_approved>1</wp:comment_approved>
        <node></node>
        <node></node>
    </wp:comment>
    <wp:comment>
        <node>ble</node>
        <node>blu</node>
        <wp:comment_approved>0</wp:comment_approved>
        <node></node>
        <node></node>
    </wp:comment>
</xml>

This is the syntax for regex find in the xml in Sublime Text:

(?s)<wp:comment>(?:(?!<wp:comment>).)+?<wp:comment_approved>0.+?</wp:comment>

(?s)           -> global search and multiline
<wp:comment>   -> find occurrence
(?: ... )      -> group but do not capture submatch 
(?! ... )      -> negative lookahead
<wp:comment>(?:(?!<wp:comment>).)+? 
               -> find <wp:comment> plus everything 
                  until a new <wp:comment> starts. 
                  This is for not select two or more comments 
                  in one time.
<wp:comment_approved>0.+?</wp:comment> 
               -> then find '<wp:comment_approved>0' 
                  Plus everything, then find </wp:comment>.

So:

first find the start (main pattern) then

find everything but not a new start

find the sub pattern

find the rest

find the end (main pattern)