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Unexpected behavior with anchor and word boundary regex

See original GitHub issue

/^./ does not highlight anything, but it should highlight the first letter. /\b./ highlights all English letters, but it should highlight the first letter.

  • I haven’t investigated why /^./ is not highlighting everything.
  • \b highlighting everything is because when each match is highlighted, the highlighted text is no longer in the textContent of the node. When the regex is applied again, \b will match the second letter, as the first letter is no longer there. This repeats until all English letters are highlighted.

Steps to reproduce

Enter in the above regex in this fiddle:


Latest version of Chrome and version 8.1.1 of jquery.mark.min.js

Proposed Fix

Psuedocode to go in wrapMatches function:

text = node.textContent  // save text because we don't want it changing each highlight
if no global flag: // highlight first match
    match = regex.exec(text)
if global flag: // highlight all matches
    while(match is not null):
        match = regex.exec(text)

Issue Analytics

  • State:closed
  • Created 7 years ago
  • Comments:5 (2 by maintainers)

github_iconTop GitHub Comments

Mottiecommented, Sep 18, 2016

It looks like /^./ is matching whitespace, so that’s why it doesn’t look like anything was found.

julmotcommented, Sep 22, 2016

@Almenon Sorry for my late reply, I was on a journey.

I can understand your situation and I agree that strictly speaking this might be expected by a small group of users. But this requirement is uncommon and the expected behavior technically impossible. We’re not searching inside a simple string like you’ve demonstrated. We’re searching inside real DOM text nodes and matches need to be wrapped. Once you’ve wrapped one match you need to search in the remaining text node value and as this is a “new” RegExp context, it will find further characters. Also, the RegExp will be applied through different text nodes, so there won’t be any chance to correctly match multiline or global matches. Therefore the limit option exists.

I’m sorry to disappoint you but I don’t see any way to resolve your request. Since this regular expression probably just exists while typing in a complete one, you might implement a method that ignores such things.


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