InDesign GREP chart

Just wanted to say I'm enjoying this discussion in the deep end of the swimming pool. I'm enjoying the learning, and it gives me insights when teaching GREP to others. Thanks James, Mark, Peter, Robert, and all you code-oriented folks on this extraordinary forum!

@James Gifford—NitroPress Thanks for the chart. And although this thread has become nearly impossible to follow in any navigational way, all that back and forth discussion about \K has finally, I think, given me an understanding of the functional use for it, so thanks to all the folks who chimed in about that, too.

James, I applaud your neat and orderly layout presentation. It looks nice.

This is the way I have been describing it (\K) in my GREP code list:

Lookbehind (keep text found out of match) ............. \K

Do you think that should be rewritten for better clarity?

@James Gifford—NitroPress 

James -- Just one small comment on your excellent chart: in the Character-class box the label for \x{■} says "Hex Code (2 or 4 digit)", but that can be 1- or 3-digit too. You can omit leading zeros: \x{9} finds tab characters, \x{14b}, the eng. It's no big deal, but maybe say '1-4 digits'.

P.

Hi @James Gifford—NitroPress, thanks for posting this. I think it's great!

I'd make one observation: that the explanation for \K is surprisingly difficult to understand for me. A clearer description, in my opinion, would be "Reset Match" or something like that. The K is usually referred to as "keep out" but that doesn't help my mental model because what it actually does is discard the current match and start again. In fact "discard" might be a good word to use. Anyway, with that in mind, the explanation via the asterisk is quite opaque, at least to me.

Otherwise, thanks for sharing.

- Mark

Edit 2025-02-16: changed "keep" to "keep out" which I hadn't remembered fully (probably due to it not really being a good explanation for what it actually does! 😛 ).

Thanks for the feedback, suggestions and contributions (through multiple channels) so far.

To make it clear, I don't intend this to be the most complete reference to GREP — not by a long shot. For one thing, the whole feature/topic is so vast and murky that there's always-always one more obscure command, another useful combo string, another trick, another limitation, etc. And we know there are many-many reference sheets, sites, pages, forums and books... some of which are even specific to InDesign's slightly specialized implementation.

But in going from "had a little memorized knowledge" to a fairly confident GREP journeyman over the last year, I've found the GREP "support" world to be like many others, in that there are many levels of understanding (quite a few of which are way beyond ID's uses), endless references of one kind or another, and the usual mix of reliability, currency and accuracy.

So I did what I do for a living (more or less, broadly speaking, all that) and created my ideal of a GREP reference, which aimed to be complete (to a specific degree), accurate (all the commands tested and the boilerplate descriptions corrected and expanded, as necessary), compact (instead of pages and pages of stuff) and, I'd hope, tidily and attractively presented. My aim was a sheet that would be of use for users across the range from "just took the training wheels off" through fairly sophisticated experts... but NOT being a tutorial for absolute newcomers or including every esoteric command/option that takes master-level experience to use. A sort of middle range tool, useful to remind the experienced and help expand the newcomers's grasp of the options. (And, without any intent to be Anglocentric or exclusionary, focused on English/Western users. I find the "let's include everyone" model of fonts, references, character/glyphs etc. a bit overwhelming given that much of that content only applies to a small percentage of users... who are usually comfortable with finding more specific support that isn't cluttered with Western specifics. 🙂 )

I wanted to limit the content to some core set of info, to keep it from being overwhelming or (as are many such references, especially from the Linux/programming side of things) filled with cryptic descriptions and notes. I left out POSIX, for example, because while some have it in their toolbox, it's largely redundant against more fundamental GREP commands. I left out back references and variables as much for space as for their being very complex concepts to put to use in GREP strings.

in short, I was aiming at a complete (to a useful level), accurate (devoid of some of the repeated errors or misleading descriptions found out there), clear (substituting clear descriptions for code-monkey-speak) and usable (clearly showing string formatting, for example) ref that was not overwhelming in content or presentation.

Continuing feedback welcome. 🙂

@Marc Autret's version:

https://www.indiscripts.com/blog/public/data/idcs4-special-characters/en_InDesignCS4-CS5-SpecialChars.pdf

Is missing "\W" - and maybe more from your list - but there are few extra codes - like Text Variables and Arabic/Hebrew/Bidi.

Many thanks for this James. 

What about all those posix-es - like "[[:punct:]]"?