RegExp: Lookaround doesn't support? -- look ahead / look behind regular expressions don't work

[Ovg]

Hi all RegExp Guru!

I got an error :

Code: Select all

Invalid file name specified! 
^((?!_h).)*$

TRegExprW(comp): Urecognized Modifier (pos 7)

What am I do wrong? This is a bug of feature?
https://yadi.sk/i/eco-pCGbAY7iAw

This RegExp working fine in UltraEdit

TC 9.21a x86/x64

[Horst.Epp]

Your link doesn't work.
So what are you doing in TC to get that error ?

[Ovg]

I'm trying to search for files using regexp
https://yadi.sk/i/eco-pCGbAY7iAw

[Stefan2]

For in TC used RE-syntax see >> http://www.ghisler.ch/wiki/index.php/Regular_Expressions

Documentation of the used RegEx-engine >> https://regexpstudio.com/en/regexp_syntax.html






 

[Horst.Epp]

I'm trying to search for files using regexp
https://yadi.sk/i/eco-pCGbAY7iAw

Lets see what RegEx experts or Christian say.
Works at least using Everything syntax.
Go to the starting dir and enter
ed:regex:^((?!_h).)*$

[Ovg]

It seems look ahead / behind doesn't support?

[Stefan2]

It seems look ahead / behind doesn't support?

That's right, it's not supported by the RE-engine TC uses. For more info search the forum for 'lookaround'




 

[Ovg]

Ok. Thank you!
I will change topic name.

[ghisler(Author)]

Sorry, the used RegEx engine doesn't support it.

[Ovg]

ghisler(Author)
Thank you for confirming this!

[alexblade]

HI guys
I have the same error

TRegExpr: Unrecognized modifier

as understand , this is because TC is using an old (not popular) TRegExp engine by Andrey V. Sorokin [ http://regexpstudio.com/ also is no more supported ]

may be Author can change regex engine to PCRE ? or may be you know how I can change it for Lister ?

and second question how I should edit my pattern to avoid error and have correct result ?

Code: Select all

:\/\/(?!.*www\.google)\S{6}

thank you

[tuska]

Hi,

TRegExp engine by Andrey V. Sorokin [ http://regexpstudio.com/ also is no more supported ]

TRegExpr by Andrey V. Sorokin is supportet: https://regex.sorokin.engineer/

'Everything' uses 'Perl Compatible Regular Expressions (PCRE)' and can be used for search queries in TC (see my signature).
See also point 3. RegEx - Regular Expressions from "Search queries: TC <=> 'Everything'" (link in signature).

Regarding RegEx-code, I'm afraid I can't help you.

---

Windows 10 Pro (x64) Version 1909 (OS build 18363.836)
TC 9.51 x64/x86 | 'Everything'-Version 1.4.1.983 (x64)
☑ 'Everything' | Search queries: TC <=> 'Everything'

[narium]

I have the same problem (TC 9.51 64bit), I tried to use the negative lookbehind as explained in https://regex.sorokin.engineer/en/latest/regular_expressions.html#assertions
but the exact example from the TRegExpr gave the "TRegExpr(comp): Urecognized Modifier (pos 7)" error.

Is this an error of TRegExpr or of TotalCommander? Is the TRegExpr library in TC up to date?

[ghisler(Author)]

The TRegExpr library does not support look ahead or look behind. It is no longer maintained.

[gdpr deleted 6]

The TRegExpr library does not support look ahead or look behind. It is no longer maintained.

That's not quite true.

The current TRegExpr library does support lookahead and lookbehind assertions (as the post you responded to already pointed out: https://regex.sorokin.engineer/en/latest/regular_expressions.html#assertions).

And it is still (again?) being maintained (https://github.com/andgineer/TRegExpr). Dunno, maybe the project was on hiatus for some time, but it seems the library is being maintained on Github for at least the last 3..4 years again.

Also, according to the man himself (Andrey Sorokin, also owner of the TRegExpr Github repo), TRegExpr has become part of Lazarus (as per the readme.md on Github).

I haven't gone through the history of the Github repo in detail, but at first glance it appears assertions were included in TRegExpr around 2019~2020, i guess...