Possible RegEx error in Sigil (minimal match being ignored)

KarlG · 08-18-2024, 09:45 AM

Hello,

I'm trying to delete all 'span' tags with no content (i.e. <span blah blah>(nothing here)</span> by using the following RegEx (with minimal match enabled)

<span .*></span>

Here is some example text which shouldn't match anything

<hgroup><h2 class="CHAPTER" id="ch1"><span class="CN"><samp class="SANS_Futura_Std_Bold_Condensed_B_11">1</samp></span> <span class="CT"><samp class="SANS_Dogma_OT_Bold_B_11">WINDOWS FOUNDATIONAL CONCEPTS</samp></span></h2></hgroup>

As we can see, there are no span tags without content. Running this RegEx however matches the following text (as can be seen in the attached screenshot)
<span class="CN"><samp class="SANS_Futura_Std_Bold_Condensed_B_11">1</samp></span>

Is there anything I have missed, or is this indeed an error?

Rgds

Karl

Doitsu · 08-18-2024, 11:29 AM

The .* in your regular expression also matches other tags. The following expression should work:

Code:

<span[^>]*></span>

KarlG · 08-18-2024, 11:34 AM

Quote:

Originally Posted by Doitsu

The .* in your regular expression also matches other tags. The following expression should work:

Code:

<span[^>]*></span>

But surely when 'minimal match' is selected, the search should also stop with the first '>'.?

DiapDealer · 08-18-2024, 01:02 PM

Nope. Minimal Match can't affect the inherent greediness of *.

At least I don't recall it doing so in the past.

KarlG · 08-18-2024, 01:12 PM

Quote:

Originally Posted by DiapDealer

Nope. Minimal Match can't affect the inherent greediness of *.

At least I don't recall it doing so in the past.

Hmm, maybe confusion on my part here then.

So what IS 'minimal match' for then, and what's the option (if there is one) for a non-greedy RegEx in Sigil?

DiapDealer · 08-18-2024, 01:29 PM

Doitsu's regex was an example of a non-greedy search. But let me do some investigation. I don't really use the Minimal Match option, so there could be a problem with it. I don't want to be too nasty in dismissing what might be a bug.

KevinH · 08-18-2024, 01:38 PM

And no the text search will only stop at the first ">" when a match is found, without a match it will continue to grow the search area until it finds the first match or none at all. That is what the "minimal match" flag means. It finds the minimal length match if one exists.

DNSB · 08-18-2024, 02:40 PM

Personally, I find it easier to use @DiapDealer's TagMechanic plugin for this type of task. Saves me from the issues when my fat fingers cause a typo,

recook · 03-02-2025, 08:11 AM

Hi,
with Sigil 2.4.2 the bug seems gone, `<div .*</div>` grabs
* without MinimalMatch in Regex Options until the last possible end of pattern,
* with MinimalMatch in Regex Options until the next possible end of pattern.

KevinH · 03-02-2025, 08:27 AM

There was no bug. See my earlier post about how minimal match actually works.

08-18-2024, 09:45 AM	#1
KarlG Connoisseur Posts: 62 Karma: 10 Join Date: Mar 2024 Device: none	Possible RegEx error in Sigil (minimal match being ignored) Hello, I'm trying to delete all 'span' tags with no content (i.e. <span blah blah>(nothing here)</span> by using the following RegEx (with minimal match enabled) <span .></span> Here is some example text which shouldn't match anything <hgroup><h2 class="CHAPTER" id="ch1"><span class="CN"><samp class="SANS_Futura_Std_Bold_Condensed_B_11">1</samp></span> <span class="CT"><samp class="SANS_Dogma_OT_Bold_B_11">WINDOWS FOUNDATIONAL CONCEPTS</samp></span></h2></hgroup> As we can see, there are no span tags without content. Running this RegEx however matches the following text (as can be seen in the attached screenshot) <span class="CN"><samp class="SANS_Futura_Std_Bold_Condensed_B_11">1</samp></span>* Is there anything I have missed, or is this indeed an error? Rgds Karl Attached Thumbnails

08-18-2024, 11:29 AM	#2
Doitsu Grand Sorcerer Posts: 5,679 Karma: 23983815 Join Date: Dec 2010 Device: Kindle PW2	The .* in your regular expression also matches other tags. The following expression should work: Code: <span[^>]*></span>

08-18-2024, 01:02 PM	#4
DiapDealer Grand Sorcerer Posts: 28,338 Karma: 203719142 Join Date: Jan 2010 Device: Nexus 7, Kindle Fire HD	Nope. Minimal Match can't affect the inherent greediness of . At least I don't recall it doing so in the past. Last edited by DiapDealer; 08-18-2024 at 01:07 PM.*

08-18-2024, 01:38 PM	#7
KevinH Sigil Developer Posts: 8,437 Karma: 5702578 Join Date: Nov 2009 Device: many	And no the text search will only stop at the first ">" when a match is found, without a match it will continue to grow the search area until it finds the first match or none at all. That is what the "minimal match" flag means. It finds the minimal length match if one exists. Last edited by KevinH; 08-21-2024 at 05:40 PM.

03-02-2025, 08:11 AM	#9
recook Enthusiast Posts: 38 Karma: 10 Join Date: Aug 2018 Device: kobo Nia	Hi, with Sigil 2.4.2 the bug seems gone, `<div .</div>` grabs without MinimalMatch in Regex Options until the last possible end of pattern, * with MinimalMatch in Regex Options until the next possible end of pattern. Last edited by recook; 03-02-2025 at 08:11 AM. Reason: double sig

08-18-2024, 01:29 PM	#6
DiapDealer Grand Sorcerer Posts: 28,338 Karma: 203719142 Join Date: Jan 2010 Device: Nexus 7, Kindle Fire HD	Doitsu's regex was an example of a non-greedy search. But let me do some investigation. I don't really use the Minimal Match option, so there could be a problem with it. I don't want to be too nasty in dismissing what might be a bug.

08-18-2024, 02:40 PM	#8
DNSB Bibliophagist Posts: 44,466 Karma: 167726775 Join Date: Jul 2010 Location: Vancouver Device: Kobo Sage, Libra Colour, Lenovo M8 FHD, Paperwhite 4, Tolino epos	Personally, I find it easier to use @DiapDealer's TagMechanic plugin for this type of task. Saves me from the issues when my fat fingers cause a typo,

03-02-2025, 08:27 AM	#10
KevinH Sigil Developer Posts: 8,437 Karma: 5702578 Join Date: Nov 2009 Device: many	There was no bug. See my earlier post about how minimal match actually works.

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