Questions tagged [regular-expressions]
is for patterns specifying search or replace strings. Also known as `regex` or `regexp`, the patterns describe strings to match when searching or replacing. Emacs provides extensive support for `regex` patterns in many commands. Emacs also provides an interactive expression builder for such patterns.
483
questions
0
votes
1
answer
36
views
How to search regex in a url-retrieve buffer?
I'm trying to implement a login system with emacs lisp, the login system has a hidden input field that's initially empty and is filled by a piece of javascript code when submitting.
I'm currently ...
- 103
0
votes
0
answers
57
views
Use different font for math fragments in org mode
How do I use the fixed-pitch font for math fragments in org-mode buffers? I.e., I want to use a monospace font for all strings of the form \(...\) or \[...\], where ... may include newline characters ...
0
votes
2
answers
48
views
How can a regex replace that computes the replacement in a function using back references be converted to a CLI batch version processing line by line?
An example of this is a script to output the contents of .zsh_history file in the manner of the history command, so an emacs script would be invoked by a command line like display.sh.el < ~/....
- 1,371
0
votes
1
answer
101
views
Am I using "replace-regexp-in-string" the right way?
I want to view ~/.zsh_history files the way they are displayed by the history command with raw unixtimestamps converted to properly formatted dates.
: 1568128379:0;cp -a ~/.zshrc.pre-oh-my-zsh ~/....
- 1,371
0
votes
1
answer
35
views
In an Elisp regexp, does anchor `^` not work with new line in front?
In an Elisp regexp, when I want to specify a pattern across two consecutive lines, I found that ^J^.* (^J is new line, and ^ is anchor of the beginning of a line) doesn't work, but ^J.* works. I was ...
- 4,987
0
votes
0
answers
44
views
Regexp searches that repeatedly cover expressions
I'm just going through an old Latex-text I've written and wanted to use regexp-replace to make any pair of brackets containing at least one other pair of brackets into a \left(.*\right)-expression. ...
0
votes
1
answer
23
views
Define new comment style with string literals rather than characters
I am trying to define another comment style, similar to what we can do with modify-syntax-entry:
(modify-syntax-entry ?/ ". 124b")
(modify-syntax-entry ?* ". 23")
(modify-syntax-...
- 135
1
vote
1
answer
47
views
How to add numbers to all lines matching a certain regex?
I have a Markdown file like this:
# Title
## My Theme
Pellentesque dapibus suscipit ligula.
### Mine is yours
Donec posuere augue in quam.
## Your Theme
* Suspendisse potenti.
* Aenean in sem ac ...
- 1,311
0
votes
1
answer
37
views
Is the '$' (end of line anchor) somehow concurrent with the '\n' (newline)? Please explain these results
In normal regex, I would expect the following to be true:
(should (equal (string-match "^abc$\nx" "abc\nx ") 0)) ;; nope! nil
(should (equal (string-match "^abc\n$x" &...
- 101
0
votes
1
answer
44
views
replace nth-match of a regexp in a string
I'm looking for a function that can replace the nth-match in a string.
Here's an example. 2 is the index of the nth-match, [0-9]+ is the regular expression to search. foo is the replacement and "...
- 408
1
vote
1
answer
39
views
function needed to replace short, static list of keywords
In my workflow I copy emails into an orgmode file. I'd like to have head of the email formatted. In english emails (just as an explanation) I'd like to have *To:* instead of To:, because orgmode then ...
- 508
1
vote
2
answers
56
views
How can I make occur display only first line of match?
The context for this is that I was trying to write a function to help me write LaTeX, specifically I'd like to list all the future references, i.e. when you use a \ref{<something>} before \label{...
0
votes
1
answer
29
views
Strange behavior with replace-regexp
I have the following line:
#ifdef DCC_3D_HPP || DCC_2D_HPP
I want to replace it with:
#if defined(DCC_3D_HPP) || defined(DCC_2D_HPP)
I use the following prompt with replace-regexp:
#ifdef \([A-Z0-9_]+\...
- 157
1
vote
0
answers
43
views
How can I search for CamelCase words in a buffer using Elisp?
How can I find CamelCase words in the buffer using Elisp?
Have started with the following but the pattern does not cover all situations of CamelCase.
(defun detect-camel-case-words (string)
"...
- 1
0
votes
1
answer
51
views
Is there a literal-string version of "looking-at"?
The function looking-at matches a regex, in some cases however I want to match against a literal string. While (looking-at (regexp-quote text)) works, it seems like there might be a way to do this ...
- 8,556
0
votes
1
answer
49
views
build regexp in lisp [duplicate]
Is there a package that provides a clearer syntax for building complicated regexes in code?
I currently have in my .emacs this regex, which matches various Java package names:
"\\(com\\.example\\|...
- 497
0
votes
3
answers
75
views
How to delete all the files matching regular expression in elisp?
I want to make some clean-up with auto-generated files. How can I delete all the files matching some regexp mask from within elisp?
As an example of desired functionality... Something like the line ...
- 125
0
votes
1
answer
36
views
Multiple regexp replace in string
I need to search for every declared variable in a string with format %^{var}, prompt a value and replace in place.
(let ((primitive "(%^{size}, %^{center})"))
(if (string-match "%^{\\(...
0
votes
1
answer
24
views
Regexp for first consecutive non whitespace ending with @?
I have a mailing list whose lines contain garbage characterized by spaces, like this:
bar qux [email protected]
for which I want to extract [email protected]. I tried this unsuccessfully:
M-x query-replace-...
user19777
1
vote
1
answer
32
views
Trouble maintaining buffer position when using re-builder
I am having trouble maintaining my current location in a document while running the re-builder command in Emacs. In a long document the buffer moves to the top of the document whenever I run the re-...
- 1,177
0
votes
1
answer
36
views
isearch-forward-regex does not find a regex found by re-builder
I wanted to create a regex to find these dates:
1966/08/20
2023/02/12
In re-builder I was able to build this:
"\([0-9]\{4\}\)/\([0-9]\{2\}\)/\([0-9]\{2\}\)"
In the buffer the dates are ...
- 1,177
0
votes
1
answer
69
views
How to use regular expressions with helm-projectile-grep?
I would like to find all strings in files matching the pattern foo_*_bar. I know that one can use \s to match empty characters. What's the pattern for zero or more characters? Could not find it by ...
- 181
1
vote
2
answers
74
views
How to align a region on &?
I thought M-x align-regexp & 1 1 y on the region containing &'s would align all columns, but it does not, so I must be using it wrong. What is the correct way? Reminder: man says white spaces ...
user19777
0
votes
2
answers
63
views
Is it possible to refile using regexp applied to some property?
If I do M-x org-refile on qux using the first (commented out) version of org-refile-targets, it brings up Foo, as expected. Using the second version, I get "No refile targets", whereas I ...
user19777
0
votes
0
answers
21
views
Highlighting strings in Org and Markdown mode doesn't work with *bold* or /italic/
I want to highlight strings between double quotation marks in org-mode and markdown-mode, just so they're easier to see, as in LaTeX-mode. I have the following in my .emacs:
;; Highlight strings ...
0
votes
0
answers
31
views
How to align source code section in both Org-src-edit-code, Org-mode, and exported PDF file?
How to configure emacs such that code (in this case :which-key) is aligned in both org-edit-src-code org-mode and exported PDF?
I'm guessing this is somewhat related to tabs getting different amount ...
- 589
2
votes
2
answers
59
views
Colourize buffer names differently for the files located in different directories
I am working upon 2 projects that have similar structure. And sometimes occasionally modify a file in the wrong buffer.
So I desided to set different colours for the files in the different projects:
(...
- 1,059
0
votes
1
answer
57
views
How to set `org-agenda-files` depending current date in order to lessen number of files to load?
I use org-roam-dailies for my TODO lists for given day. And currently, I set my org-agenda-files to org-roam-dailies's directory as below:
(setq org-agenda-files '("~/roamnotes/daily/"))
...
- 589
0
votes
2
answers
127
views
Regex to find and replace a specific character inside of multiple quoted strings in a string
Given an example string of JSON (formatted here for reading, actual input may or may not be formatted):
{
"page":1,
"per_page":6,
"total":12,
"...
- 126
0
votes
1
answer
26
views
searching for <beginningOfLine><Comma>
how can I (interactive) search for <beginningOfLine>,
I tried ^ which means beginning of line in perl
Also \A which does signified the same in ruby.
C-s ^,
C-s \A,
I also tried search-forward-...
- 3,853
1
vote
1
answer
125
views
What is the replace regexp string for applying 3 digit grouping to any number?
the title gives it all away:
I want this
9874599842006432.08
To become this
9,874,599,842,006,432.08
with 1 single replace regexp operation and flexible,
so that the same string also would work on a ...
- 53
2
votes
3
answers
53
views
How to programatically determine which alternative of a regular expression is responsible for a match?
Suppose I have a regular expression with many alternatives, such as
"[a-z]+\\|[A-Z]+\\|[0-9]+"
and it has just matched some text. I'd then like to know which of the given alternatives ...
- 839
0
votes
1
answer
41
views
Why do Emacs Lisp regular expressions match the percentage and dollar sign as word characters?
I ran into this behavior by accident and it seems quite unusual to me.
Why do Emacs Lisp regular expressions match the percentage and dollar sign as word characters?
One theory I had was that this is ...
- 141
2
votes
1
answer
96
views
Why "looking-back" does not match "[ \n]+"?
I want to do this replacement:
\includegraphics{file
}
==>
\includegraphics{file}
I wrote this code:
(goto-char (point-min))
(while (re-search-forward "\\\\includegraphics{" nil ...
- 431
0
votes
1
answer
36
views
"-o" like options for `elgrep`?
Sometimes I just want the matched result by regexp instead of the whole line, this seems possible via the -o option in grep
I discovered elgrep in emacs recently, which is fantastic! Any chance we can ...
- 127
0
votes
0
answers
25
views
Change foreground colour or files showing error in rsync log file
I want to colour the file names that are logged with an error when using rsync.
One such file will be as follows
2022/12/07 21:33:49 [3672] WARNING: b2-infocs/unix-like/2006-hagan-gcc.pdf failed ...
- 1
0
votes
1
answer
47
views
Using general comment character used in programming languages
I am using highlight-regexp with a regexp pattern that includes the elisp comment characters ;;. How can I extend the pattern so that it adequately handle the general comment character for each ...
- 1
1
vote
1
answer
72
views
Using a sub-expression for `highlight-regexp`
I have made a face to highlight elisp comments starting with ;; [ using hi-lock. My intention is to only colour the expression [text] using SUBEXP.
(highlight-regexp "^;; \\[.+\\].+$" 'face-...
- 1
0
votes
0
answers
16
views
emacs multiple regex apropos
If I use apropos-command or apropos-documentation it prompts me for a word list or a regex.
In the command line, apropos allows for multiple regexes where it only shows matches that match all the ...
- 49
1
vote
1
answer
10
views
Switch a TeX \macro and a script on a region of text
How can I search and replace in a region of a (TeX)buffer all occurences of \macro{foo}_{bar} to \macro{foo_{bar}}, foo and bar not being "constants" ?
- 197
0
votes
1
answer
34
views
Weird behavior of `search-forward-regexp` influenced by buffer mode change
Action 1: evaluate the lisp expression: (search-forward-regexp "\\s'")
in a buffer in lisp-interaction-mode containing the text:
The pandemic market was cooling, but homes in north Seattle ...
- 839
0
votes
1
answer
64
views
Highlight query-replace-regexp results while searching
I am terrible at remembering regular expression syntax. When replacing in by buffer with a regexp, I would like Emacs to highlight the possible matches while I am typing the regexp, so that I can see ...
0
votes
1
answer
89
views
Does any package exist that can make interactive emacs-style regular expressions more readable by using font-locking?
Ideally the package would allow one to display emacs-style regular expressions, as they are entered interactively during a search and replace command, in a more human-readable form.
Perhaps fewer ...
- 133
1
vote
1
answer
40
views
regexp-isearch with fixed prefix
I'd like to search a buffer for headlines only. A headline is anything starting with the "*" character. Ideally, I'd invoke an interactive function which would take user input at the ...
- 207
0
votes
1
answer
34
views
regexp string matching a single word
I am looking to match the word as on its own and am using
(s-replace-regexp "\\<as\\>" "s" word)
Is this the way to it?
- 1
0
votes
2
answers
45
views
Replacing words using multiple rules
This function is supposed to replace matches with a shortened version using multiple rules rather than just a single one. For the word counter, coun gets replaced by k, resulting in the shortened ...
- 1
0
votes
1
answer
41
views
Using rx to insert word replacement
Been working on replacing regexps with the equivalent rx command, but the expression for rx is not producing the same result I get with the regexp. For the word counter, the regexp expression gives ...
- 1
0
votes
0
answers
93
views
Replacing single prefix from word
I want to omit the beginning of words starting with some (e.g. something changed to thing).
This is the way I am doing it
(insert (replace-regexp-in-string "\\<\\(some\\)" "" ...
- 1
0
votes
1
answer
44
views
Using query-replace-regex to partially replace
I'm struggling with the basics of query-replace-regex after reading the manual.
I'm trying to replace lots of citations formatted like this:
#123213213, foo bar
to
#123213213\, foo bar
the numbers ...
- 113
0
votes
1
answer
48
views
Is it possible to mimic sed's "change line" feature?
I'd like to write an elisp function that allows me to replace any line in my buffer matching a regex pattern <PATTERN> with text <TEXT>. In other words, if line N matches <PATTERN>, ...
- 2,285