I want to search a HTML tag in my html file using Vim.
I tried \<html\> but it means search only the “html” word.
I don’t know how to find the greater or lower characters.
Vim has 4 modes of regular expression interpretation:
very no magic,
no magic,
magic and
very magic.
The default is magic (check with :set magic?), which can be a bit surprising because some non alphanumeric characters have special regex meanings but not all. In particular ^$*. do but most other characters do not. For example to match alternatives you'd have to escape the pipe character this\|that and this|that would match the literal string "this|that".
In your case, < does not have a special meaning but \< does (beginning of a word). Searching for <html> will work, but when in doubt you can activate "very no magic" mode by prepending your search with \V (so /\V<html>) where every character matches the character itself. If and when you want to activate all regex features, you can activate "very magic" mode with lowercase \v (hence /\v<html> will search for the word "html").
In Normal mode, the / command searches forward (? — backward). Suppose we are at the top, and want to search forward. So, if we want to find a particular tag, like “div” for example, we should type the following:
/\V<div>
Here \V turns on the ”very unmagic” mode in which a symbol has no any special meaning unless it is preceded by a backslash. (I use only the “very magic” and “very unmagic” modes and don’t use the “magic” and “unmagic” modes.)
If we want to find any html tag, i.e. something between angle brackets, we may type one of the following:
/\V<\[^<>]\+>
/\v\<[^<>]+\>
That will find and highlight all the tags including their attributes.
You may create a convenient keymap for the mode you prefer, for example:
nnoremap // /\V
Now, double hitting of / brings you to the search line with “very unmagic” mode.
Type :help pattern for more information.
Related
I'm trying to convert multiple instances of Unicode codes to their corresponding characters.
I have some text with this format:
U+00A9
And I want to generate the following next to it:
©
I have tried to select the code in visual mode and use the selection range '<,'> in command mode as input for i_CTRL_V but I don't know how to use special keys on a command.
I haven't found anything useful in the manual with :help command-mode . I could solve this problem using other tools but I want to improve my vim knowledge. Any hint is appreciated.
Edit:
As #m_mlvx has pointed out my goal is to visually select, then run some command that looks up the Unicode and does the substitution. Manually input a substitution like :s/U+00A9/U+00A9 ©/g is not what I'm interested in as it would require manually typing each of the special characters on every substitution.
Any hint is appreciated.
Here are a whole lot of them…
:help i_ctrl-v is about insert mode and ranges matter in command-line mode so :help command-mode is totally irrelevant.
When they work on text, Ex commands only work on lines, not arbitrary text. This makes ranges like '<,'> irrelevant in this case.
After carefully reading :help i_ctrl-v_digit, linked from :help i_ctrl-v, we can conclude that it is supposed to be used:
with a lowercase u,
without the +,
without worrying about the case of the value.
So both of these should be correct:
<C-v>u00a9
<C-v>u00A9
But your input is U+00A9 so, even if you somehow manage to "capture" that U+00A9, you won't be able to use it as-is: it must be sanitized first. I would go with a substitution but, depending on how you want to use that value in the end, there are probably dozens of methods:
substitute('U+00A9', '\(\a\)+\(.*\)', '\L\1\2', '')
Explanation:
\(\a\) captures an alphabetic character.
+ matches a literal +.
\(.*\) captures the rest.
\L lowercases everything that comes after it.
\1\2 reuses the two capture groups above.
From there, we can imagine a substitution-based method. Assuming "And I want to generate the following next to it" means that you want to obtain:
U+00A9©
you could do:
v<motion>
y
:call feedkeys("'>a\<C-v>" . substitute(#", '\(\a\)+\(.*\)', '\L\1\2', '') . "\<Esc>")<CR>
Explanation:
v<motion> visually selects the text covered by <motion>.
y yanks it to the "unnamed register" #".
:help feedkeys() is used as low-level way to send a complex series of characters to Vim's input queue. It allows us to build the macro programatically before executing it.
'> moves the cursor to the end of the visual selection.
a starts insert mode after the cursor.
<C-v> + the output of the substitution inserts the appropriate character.
That snippet begs for being turned into a mapping, though.
In case you would like to just convert unicodes to corresponding characters, you could use such nr2char function:
:%s/U+\(\x\{4\}\)/\=nr2char('0x'.submatch(1))/g
Brief explanation
U+\(\x\{4\}\) - search for a specific pattern (U+ and four hexadecimal characters which are stored in group 1)
\= - substitute with result of expression
'0x'.submatch(1) - append 0x to our group (U+00A9 -> 0x00A9)
In case you would like to have unicode character next to text you need to modify slightly right side (use submatch(0) to get full match and . to append)
In case someone wonders how to compose the substitution command:
'<,'>s/\<[uU]+\(\x\+\)\>/\=submatch(0)..' '..nr2char(str2nr(submatch(1), 16), 1)/g
The regex is:
word start
Letter "U" or "u"
Literal "plus"
One or more hex digits (put into "capture group")
word end
Then substituted by (:h sub-replace-expression) concatenation of:
the whole matched string
single space
character by UTF-8 hex code taken from "capture group"
This is to be executed in Visual/command mode and works over selected line range.
I used this map:
map ,w v/\([^ a-z0-9]\|[^ A-Z0-9]\)*<cr>h
the idea is to select
in the words
mysuperTest
MYSUPER_TEST
mysuper_test
to always select the part that says mysuper
but it doesnt work, not sure why
I would use something like the below:
nnoremap ,w v/\C\%#.\([a-z]\+\<bar>[A-Z]\+\)\zs<cr>h
One point to notice is that in a mapping you need to use <bar> (or escape | with an extra backslash) since otherwise | is recognized as a command separator (see :help map-bar.)
Another one to notice is that you want the match to start at the first character outside the word (so you'll land at the end of the word with the h). The visual selection will expand to the start of the match in a search. I suggest using \zs to set the start of the match explicitly (see :help /\zs.)
Finally, beware of 'ignorecase' or 'smartcase' settings. Use \C to explicitly request a case-sensitive match (see :help /\C.)
I also like the idea of using a stronger anchor for the start of the match, so I'm using \%# to match the current cursor position (see :help /\%#), so you're always sure to match the current word only and not end up wandering through the buffer.
Putting it all together:
\C Case-sensitive search
\%# From cursor position
. Skip first character
\( Either one of:
[a-z]\+ One or more lowercase letters
\| (\<bar>) Or:
[A-Z]\+ One or more uppercase letters
\) End group
\zs Set match position here
I'm skipping the first character under the cursor, since in a CamelCase word, the first character won't match capitalization of the remainder of the word.
I kept your original idea of finding the first character after the word then using h to go back one to the left. But that might be a problem if, for example, the word is at the end of the line.
You can actually match the last character of the word instead with something like [a-z]\+\zs[a-z], which will set the start of the match on the last lowercase character. You can do this for both sides of the group (you can have more than one \zs in your pattern, last wins.) If you structure your match that way, you won't need the final h to go back.
I didn't handle numbers, I'll leave those as an exercise to the reader.
Finally, consider there are quite a few corner cases that can make such a mapping quite tricky to get right. Rather than coming up with your own, why not look at plug-ins which add support for handling CamelCase words that have been battle-tested and will cover use cases a lot more advanced than the simple expression you're using here?
There's the excellent vim-scripts/camelcasemotion by Ingo Karkat which sets up a ,w mapping to move to the start of the next CamelCase word, but also i,w to select the current one. You can use powerful combinations such as v3i,w to visually select the current and next two CamelCase words.
You might also check Tim Pope's tpope/vim-abolish which, among other features, defines a set of cr mappings to do coercion from camelCase to MixedCase, snake_case, UPPER_CASE, etc. (Not directly about selecting them, but still related and you might find it useful.)
I'm trying to search for only a singular digit in vim by itself. For example, if there are two sets of digits 1 and 123 and I want to search for 1, I would only want the singular 1 digit to be found.
I have tried using regular expressions like \<1> and \%(a)#
You almost had the right solution. You want:
\<1\>
This is because each angled bracket needs to be escaped. Alternatively, you could use:
\v<1>
The \v flag tells vim to treat more characters as special without needing to be escaped (for example, (){}+<> all become special rather than literal text. Read :h /\v for more on this.
A great reference for learning regex in vim is vimregex.com. The \<\> characters are explained in 4.1 "Anchors".
If you want to match text like 1.23 this is possible too. Two different approaches:
Modify the iskeyword option so that it includes .. This will also affect how w moves
Use \v<1(\d|.)#!, which basically means "a 1 at the beginning of a word, that isn't followed by some other digit or a period."
In order to search for a string in Vim, I click "/" and then type the word that I have to search. Vim looks at this string as regular expression. I want to know how to search a string, as it it, and not treat it as a regex.
Search commands always search for patterns (also known as regular expressions). You can make patterns more or less magic but cannot turn metacharacters completely off. If you have a fixed string you have to escape the characters that vim understands as metacharacters.
With the very nomagic mode of Vim's regular expressions (:help /\V), only the backslash is a special character that needs escaping.
So, prepend \V to your literal search, and (either manually or via escape(pattern, '\')) duplicate any backslashes. The following turns a "regular" search in to a literal one; you could define a mapping for that:
:let #/ = '\V' . escape(#/, '\')
In vi (from cygwin), when I do searching:
:%s/something
It just replaces the something with empty string like
:%s/something// .
I've googled for a while but nothing really mentions this. Is there anything I should add to the .vimrc or .exrc to make this work?
Thanks!
In vi and vim, when you search for a pattern, you can search it again by simply typing /. It is understood that the previous pattern has to be used when no pattern is specified for searching.
(Though, you can press n for finding next occurence)
Same way, when you give a source (pattern) and leave the replacement in substitute command, it assumes that the replacement is empty and hence the given pattern is replaced with no characters (in other words, the pattern is removed)
In your case, you should understand that % stand for whole file(buffer) and s for substitute. To search, you can simply use /, followed by a pattern. To substitute , you will use :s. You need not confuse searching and substituting. Hence, no need for such settings in ~/.exrc. Also, remember that / is enough to search the whole buffer and % isnt necessary with /. / searches the entire buffer implicitly.
You may also want to look at :g/Pattern/. Learn more about it by searching :help global or :help :g in command line.
The format of a substitution in vim is as follows:
:[range]s[ubstitute]/{pattern}/{string}/[flags] [count]
In your case you have omitted the string from the substitution command and here what vim documentation stated about it:
If the {string} is omitted the substitute is done as if it's empty.
Thus the matched pattern is deleted. The separator after {pattern}
can also be left out then. Example: >
:%s/TESTING This deletes "TESTING" from all lines, but only one per line.
For compatibility with Vi these two exceptions are allowed:
"/{string}/" and "\?{string}?" do the same as "//{string}/r".
"\&{string}&" does the same as "//{string}/".
E146
Instead of the '/' which surrounds the pattern and replacement string, you can
use any other single-byte character, but not an alphanumeric
character, '\', '"' or '|'. This is useful if you want to include a
'/' in the search pattern or replacement string. Example: >
:s+/+//+
In other words :%s/something and :%s;something or :%s,something have all the same behavior because the / ; and , in the last examples are considered only as SIMPLE SEPARATOR