Sometimes, invisible characters, other than whitespaces, exist in a file. I can tell, because, even when the font is a monopitch font, when I tap the left or right arrow key, the insertion point moves only very slightly. (I don't have an example any more, so I can't demonstrate with a file for everyone to see.) I'd like a regular expression that will let me find all invisible characters other than full-width whitespaces (i.e., other than at least tabs and hard and soft spaces and other than paragraph ends). I'd also like a way to identify them, such as a place to paste them into that will tell me their Unicode values; identification of glyphs is discussed in bug 91029.
Hi @Nick I think in the icu-project, what is used by LibreOffice you can find some help to find those characters. http://userguide.icu-project.org/strings/regexp But I don't know if all Metacharacters are implemented with LibreOffice.
Considering ICU Project, what would help in LibreOffice is the putting together of a bunch of regexes into one request, such as, more or less, in the form of (\Uhhhhhhhh OR \Uhhhhhhhh OR \Uhhhhhhhh OR \Uhhhhhhhh OR \Uhhhhhhhh OR \Uhhhhhhhh OR \Uhhhhhhhh OR \Uhhhhhhhh), but I don't have a list of all those values. It would be easier to use if one regex could encompass all of the zero-character-width characters.
Perhaps a remedy or a correction: "[:cntrl:]" is already in the regex list (it's for a nonprinting character) and I can't test if it would have accomplished the same thing. I'm changing the status. If someone else has the problem and can test at least that regex, go ahead and reopen. Thanks.