Regex and named groups

[uneMule]

Bonjour à tous,
une petite questions concernant l'utilisation des noms de groupes.
La recherche fonctionne mais le remplacer renvoi le nom du groupe à la place de la valeur trouvée.
Sinon $1:$3 fonctionnement.

Hello everyone,
I have a small question about the use of named groups.
The search works but replacing it returns the group name instead of the value found.
Else $1:$3 work.

find : \<(?<hour>[0-1]?[0-9]|2?[0-3])\s?[hH]\s?((?<min>[0-5][0-9])\s?(′|min|mn)?)\>
replace : ${hour} : ${min}

Publisher 1.10.0.1098 et 1.9.2.1035

[Old Bruce]

Off the top of my head I am not sure if named groups is supported in the regular expressions for Publisher.

I should also point out that I have never used them after learning how ... (years?) ... way back when.

[uneMule]

1 minute ago, Old Bruce said:

Off the top of my head I am not sure if named groups is supported in the regular expressions for Publisher.

Good evening. Me to. I'm not sure. But the regex does not create errors. It's amazing. Is that half supported?

[walt.farrell]

43 minutes ago, uneMule said:

Hello everyone,
I have a small question about the use of named groups.
The search works but replacing it returns the group name instead of the value found.
Else $1:$3 work.

find : \<(?<hour>[0-1]?[0-9]|2?[0-3])\s?[hH]\s?((?<min>[0-5][0-9])\s?(′|min|mn)?)\>
replace : ${hour} : ${min}

Publisher uses the boost.org regular-expression library, and you can find documentation on that at https://www.boost.org/doc/libs/1_76_0/libs/regex/doc/html/index.html or specifically https://www.boost.org/doc/libs/1_76_0/libs/regex/doc/html/boost_regex/syntax/perl_syntax.html for the Perl-based regex syntax that (I think) Publisher uses.

From that, I would conclude that to refer to a named backreference you need to use \g{name} or \k<name> but neither of those seems to work, either.

[uneMule]

33 minutes ago, walt.farrell said:

From that, I would conclude that to refer to a named backreference you need to use \g{name} or \k<name> but neither of those seems to work, either.

Bonsoir @walt.farrell,
Yes, you are right. I tried that too
$<hour>
\<hour>
g\{hour}
Nothing to do.

 

33 minutes ago, walt.farrell said:

specifically https://www.boost.org/doc/libs/1_76_0/libs/regex/doc/html/boost_regex/syntax/perl_syntax.html

Quote: Finally the \k escape can be used to refer to named subexpressions, for example \k<two> will match whatever matched the subexpression named "two"

33 minutes ago, walt.farrell said:

or \k<name> but neither of those seems to work, either.

you are right too.

[walt.farrell]

After experimenting further, and reading the documentation more closely, I believe that the functions such as \g{name} and \k<name> are for use only while searching. They allow you to refer back to a prior match, so you can match the same thing again.

They are not used during Replace processing in any application I have that supports regex processing. So, for Replace processing, we need to use the usual numbered forms, \1 or $1, \2 or $2, etc.

[uneMule]

2 minutes ago, walt.farrell said:

After experimenting further, and reading the documentation more closely, I believe that the functions such as \g{name} and \k<name> are for use only while searching. They allow you to refer back to a prior match, so you can match the same thing again.

I'll dig that. Thanks. Again.

[walt.farrell]

You're welcome.

[uneMule]

@walt.farrell

Effectivement cela permet de faire de la récursivité indépendamment du rang. (?'hour'\d)(\d{2})\g{hour} trouve 4784 2132. (?'lettre'\l)\g{lettre} trouve mm cc ll... Ça peut servir.

Indeed, this allows for recursivity regardless of rank. (?'hour'\d)(\d{2})\g{hour} find 4784 2132. (?'lettre'\l)\g{lettre} find mm cc ll... This can be useful.

[walt.farrell]

With more research, this will work in Publisher:

Find: (?<HOUR>[0-1]?[0-9]|2?[0-3])\s?[hH]\s?(?<MIN>[0-5][0-9])\s?(′|min|mn)?

Replace: $+{HOUR}:$+{MIN}

We were missing the + before. Also, it works only with $ and will not work if you use \ to refer to the replacement variables.

 

[uneMule]

hi @walt.farrell

thanks. I hadn't found this information. However, I looked for...

[lacerto]

(...)

[walt.farrell]

1 hour ago, Lagarto said:

I tried to use RegexBuddy to resolve this but it seems this app is mainly useful when there is already a working syntax (in some dialect)

I found the info at http://www.regular-expressions.info/

 but it should also be available in RegexBuddy in the documentation available in the Help. The documentation lists how things are handled in various RegEx interpreters, and you can just look at the column for Boost to see if something is supported there.

[lacerto]

(...)

[uneMule]

3 hours ago, Lagarto said:

InDesign users e.g. are spoilt by an in-built expression builder and saving feature so that shared complex searches can be easily re-used

Yes, it is clear. Soon in Publisher?

@walt.farrell Thanks again. You amaze me.