Can you write unescaped search terms in the Vim command line? - vim

When I do a search and replace on a yanked line that has characters that require escaping it's really annoying to have to go back through the command line string and escape all the special characters.
Is there a way to use a literal (raw) string modifer like in python: str = r'\unescaped\'?

Use the \V modifier:
:%s/\V$foo//g
See also :help /magic

I just thought of doing this instead: :%s;\foo\;bar;g. This solves the escape the backslash problem Manni points out.

Related

why does vim has different escape character for newline between searching and replacing [duplicate]

From question How to replace a character for a newline in Vim?. You have to use \r when replacing text for a newline, like this
:%s/%/\r/g
But when replacing end of lines and newlines for a character, you can do it like:
:%s/\n/%/g
What section of the manual documents these behaviors, and what's the reasoning behind them?
From http://vim.wikia.com/wiki/Search_and_replace :
When Searching
...
\n is newline, \r is CR (carriage return = Ctrl-M = ^M)
When Replacing
...
\r is newline, \n is a null byte (0x00).
From vim docs on patterns:
\r matches <CR>
\n matches an end-of-line -
When matching in a string instead of
buffer text a literal newline
character is matched.
Another aspect to this is that \0, which is traditionally NULL, is taken in
s//\0/ to mean "the whole matched pattern". (Which, by the way, is redundant with, and longer than, &).
So you can't use \0 to mean NULL, so you use \n
So you can't use \n to mean \n, so you use \r.
So you can't use \r to mean \r, but I don't know who would want to add that char on purpose.
—☈
:help NL-used-for-Nul
Technical detail:
<Nul> characters in the file are stored as <NL> in memory. In the display
they are shown as "^#". The translation is done when reading and writing
files. To match a <Nul> with a search pattern you can just enter CTRL-# or
"CTRL-V 000". This is probably just what you expect. Internally the
character is replaced with a <NL> in the search pattern. What is unusual is
that typing CTRL-V CTRL-J also inserts a <NL>, thus also searches for a <Nul>
in the file. {Vi cannot handle <Nul> characters in the file at all}
First of all, open :h :s to see the section "4.2 Substitute" of documentation on "Change". Here's what the command accepts:
:[range]s[ubstitute]/{pattern}/{string}/[flags] [count]
Notice the description about pattern and string
For the {pattern} see |pattern|.
{string} can be a literal string, or something
special; see |sub-replace-special|.
So now you know that the search pattern and replacement patterns follow different rules.
If you follow the link to |pattern|, it takes you to the section that explains the whole regexp patterns used in Vim.
Meanwhile, |sub-replace-special| takes you to the subsection of "4.2 Substitute", which contains the patterns for substitution, among which is \r for line break/split.
(The shortcut to this part of manual is :h :s%)

Execute vim substitute command that includes '/' characters

I have a java file in which I wrote /t, instead of \t, the proper notation of the tab escape function. I want to use vim’s substitution feature (:s) but when I do something like this:
:%s//t/\t/g
I get the error message
E488: Trailing characters
How can I write the command such that I can execute the substitution? Thank you.
Use backslash to escape the characters. So:
:%s/\/t/\\t\g
You can also use a different delimiter like:
:%s#/t#\\t#g
Use colons instead of a slash to avoid confusions and errors if what you want to look-up/replace has slashes. This way VIM will be able to parse the sentence correctly. Then you need to scape the back-slash otherwise VIM will replace /t with tabulations
:%s:/t:\\t:g
Escape the forward slash in your search pattern:
:%s/\/t/\\t/g
or use another separator:
:%s;/t;\\t;g

vim string substitution

I want to substitute all cygdrive/e with cygdrive/d using vim. But I can't get the matching pattern correctly. Here is my command:
s/cygdrive\/e/cygdrive\/d/g
it doesn't work. Can anybody show me what is wrong?
Thanks,
vim allows you to specify the delimiter.. (First character after s is the delimiter)
s/cygdrive\/e/cygdrive\/d/g
using line range argument .. and # as delimiter
ESC:
:1,$ s#/cygdrive/e#/cygdrive/d#g
Your search pattern and replacement string look fine.
Make sure you are in ex mode when you try it.
So press ESC, then : and then
%s/cygdrive\/e/cygdrive\/d/g
But if you want all he replacements in just the current line you can do:
s/cygdrive\/e/cygdrive\/d/g
You have to escape the special character
like this
s/cygdrive\/e/cygdrive\/d/g

How to search and replace an unprintable character

I've a file that was exported from Word and it replaced all quotes with strange unicode characters which aren't correctly displayed in vim.
So now I want those characters to be replaced with quotes, but I don't know how to enter this character in
:%s/???/'/g
The characters look like this: ~U ~R. But of course I can't just mark them with mouse and paste in the command.
You can try setting the encoding type and see if it fixes the visalizations of those characters:
:set encoding=utf-8
then you can use them directly. Alternatively, you can place your cursor on the unprintable character and hit ga, it will show the decimal/hex/octal code of that character, then you can substitute it with:
:%s/\%xYY/substitute/g
where YY is the hex code of the char, if it's multibyte:
:%s/\%uYYYY/substitute/g
for details:
:help character-classes
Note that you can search and match with \%xff or \%uabcd but will be unable to substitute with it.
I usually:
delete the character with: x
undo my change with: u
do the substitute thanks to c_CTRL-R: :%s/^R"/'/g
you can also filter it by using the tr command
for example replacing the hex a0 which stems from MacOs cut-and-paste
can be replaced with a whitespace as follows (\240 being the octal representation of hex a0)
:.,$!tr "\240" " "

vim regexps from the perl's point of view: which special characters to escape with backslash

Imagine, we have to construct a regexp in vi/vim. Which special characters we have to escape with backslash?
By special characters I mean the following chars: {}|()-[]+*.^$?
Seems like we have to escape: {|()+?
And leave as is: }^$*.[]-
Thanks.
p.s. AFAIK, we have no '?' character in vi/vim but '=' instead which should be also escaped by backslash.
I think the Vim documentation on magic characters will give you a definitive list.
In vim:
:help magic
I think the simplest way, that will work regardless of vim's magic setting, is
let re = '\V' . escape(fixed_string, '\')
\V disables magic entirely from that point onward in the RE. This means that anything not preceded by a single backslash (well, technically by an odd number of backslashes) is a normal character. Since we escape any backslashes in the fixed string, there can be no magic characters contained in it.
Remember that with \V in effect, you have to backslash-prefix any RE meta-characters. So if you're looking for a line that entirely consists of the fixed string, you would
let full_line_re = '\V\^' . escape(fixed_string, '\') . '\$'
Also keep in mind that vim's ignorecase and smartcase settings will affect RE behaviour. The \C (case-sensitive) and \c (case-insensitive) switches work the same way as \V: they will override those settings for the part of any regexp which follows them.

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