How to split a string before a dot in Lua? - string

I need to do a simple split of a string.
The string is "That.Awkward.Moment.2014.720p.BluRay.x264.YIFY.srt"
I just need "That.Awkward.Moment.2014.720p.BluRay.x264.YIFY" without ".srt"
I tried this and is wrong:
print(string.match("That.Awkward.Moment.2014.720p.BluRay.x264.YIFY.srt", '^.-.s'))
How would I do it?

Since regular matching is greedy, you just need to match anything until you see . (don't forget to escape it):
print(string.match("That.Awkward.Moment.2014.720p.BluRay.x264.YIFY.srt", '(.+)%.(.+)'))
will print
That.Awkward.Moment.2014.720p.BluRay.x264.YIFY srt

Related

Regex remove both apostrophes if they exist in Python

I’m quit new to Regex but almost finished with my text mining script. Only one thing fails: I’m trying to remove the apostrophes between a word if they exist. I’m using re.sub for this.
For instance:
‘Apple’ needs to be Apple
‘apple’ needs to be apple
‘[apple]’ needs to be [apple]
‘(apple)’ needs to be (apple)
However: Apple’s needs to stay Apple’s because there is only one apostrophe.
How do I select both apostrophes when there is a word in between so I can delete them with re.sub? In every try I remove the entire string! Hopefully someone can help.
My code is as follows:
str_o='\'Apple\''
str_o_a = re.sub(r"\'(.*?)\'","", str_o)
I have a simpler idea: split by whitespace, trim leading and trailing apostrophes, join with whitespace. Avoids having to write a regular expression and handles sentences such as "She's 'her' mother's daughter".
text = "She's 'her' mother's daughter"
text = ' '.join([word.strip("'") for word in text.split()])
print(text)
# She's her mother's daughter
The purpose of the parentheses in your regular expression was probably to capture the string you want to keep. The idiom looks like
str_o_a = re.sub(r"'([^']*)'", r"\1", str_o)
You want a raw string around the replacement, too, in order to preserve the backslash in the argument (otherwise you would be replacing with the literal string "\x01").
Notice also the preference for using a negated character class over a non-greedy "match anything" wildcard.

Appending to the end of a pattern with a word in the middle using vim

I have a file that is out-of-date and needs to be updated. The names have changed somewhat and I would like to clean them all up using a single substitution.
Here's what I'm trying to accomplish:
foo.foo_[single word] -> foo_bar.foo_[single word]_bar
where a single word is a string of n characters. In the file, they are always preceded by an underscore, but it needs to have "_bar" appended. There is always a "." after these instances, so I thought the following might work:
%s/foo\.foo_*\./foo_bar\.foo_*_bar\./g
Sadly, the first part doesn't even match what I want, so I'm back to square one.
I would first change:
foo_[word] -> foo_[word]_bar
and then
foo. -> foo_bar.
i.e.:
%s,\(foo_\w\+\),\1_bar,g|%s,foo\.,foo_bar\.,g
There are many ways to skin a cat but following should do the trick
%s/\vfoo.foo_(\w+)/foo_bar.foo_\1_bar/gc
what loosely translates to
\v Very Magic (:help magic)
foo.foo_ Search for exact string
(\w+) Search for a "word" and store in a backreference
/foo_bar.foo Replace search pattern with this exact string
\1 appended with backreference 1
_bar appended with _bar
or if you don't want to repeat the search in the replace part, you can go a bit nuts with backreferences and use
%s/\v(foo)\.foo_(\w+)/\1_bar.\1_\2_bar/gc
The most important parts you were missing were
using backreferences (:helpgrep backref)
using character classes (:h \w)
using repetition (_* is searching for 0 or more underscores. You probably meant _.*)

vim search and replace between number

I have a pattern where there are double-quotes between numbers in a CSV file.
I can search for the pattern by [0-9]\"[0-9], but how do I retain value while removing the double quote. CSV format is like this:
"1234"5678","Text1","Text2"
"987654321","Text3","text4"
"7812891"3","Text5","Text6"
As you may notice there are double quotes between some numbers which I want to remove.
I have tried the following way, which is incorrect:
:%s/[0-9]\"[0-9]/[0-9][0-9]/g
Is it possible to execute a command at every search pattern, maybe go one character forward and delete it. How can "lx" be embedded in search and replace.
You need to capture groups. Try:
:%s/\(\d\)"\(\d\)/\1\2/g
[A digit can also be denoted by \d.]
I know that this question has been answered already, but here's another approach:
:%s/\d\zs"\ze\d
Explanation:
%s   Substitute for the whole buffer
\d   look up for a digit
\zs set the start of match here
"     look up for a double-quote
\ze set the end of match here
\d   look up for a digit
That makes the substitute command to match only the double-quote surrounded by digits.
Omitting the replacement string just deletes the match.
You need boundaries to use in regular expression.
Try this:
:%s/\([0-9]\)"\([0-9]\)/\1\2/g
A bit naive solution:
%s/^"/BEGINNING OF LINE QUOTE MARK/g
%s/\",\"/quote comma quote/g
%s/\"$/quota end of line/g
%s/\"//g
%s/quota end of line/"/g
%s/quote comma quote/","/g
%s/BEGINNING OF LINE QUOTE MARK/"/g
A macro can be created quite easy out of it and invoked as many times as needed.

Vim Search/replace: what do I need to escape?

I'm trying to search and replace $data['user'] for $data['sessionUser'].
However, no matter what search string I use, I always get a "pattern not found" as the result of it.
So, what would be the correct search string? Do I need to escape any of these characters?
:%s/$data['user']/$data['sessionUser']/g
:%s/\$data\[\'user\'\]/$data['sessionUser']/g
I did not test this, but I guess it should work.
Here's a list of all special search characters you need to escape in Vim: `^$.*[~)+/
There's nothing wrong with with the answers given, but you can do this:
:%s/$data\['\zsuser\ze']/sessionUser/g
\zs and \ze can be used to delimit the part of the match that is affected by the replacement.
You don't need to escape the $ since it's the at the start of the pattern and can't match an EOL here. And you don't need to escape the ] since it doesn't have a matching starting [. However there's certainly no harm in escaping these characters if you can't remember all the rules. See :help pattern.txt for the full details, but don't try to digest it all in one go!
If you want to get fancy, you can do:
:%s/$data\['\zsuser\ze']/session\u&/g
& refers to the entire matched text (delimited by \zs and \ze if present), so it becomes 'user' in this case. The \u when used in a replacement string makes the next character upper-case. I hope this helps.
Search and replace in vim is almost identical to sed, so use the same escapes as you would with that:
:%s/\$data\['user'\]/$data['session']/g
Note that you only really need to escape special characters in the search part (the part between the first set of //s). The only character you need to escape in the replace part is the escape character \ itself (which you're not using here).
The [ char has a meaning in regex. It stands for character ranges. The $ char has a meaning too. It stands for end-line anchor. So you have to escape a lot of things. I suggest you to try a little plugin like this or this one and use a visual search.

Why do I have to escape the final ]

I have a file containing string like this one :
print $hash_xml->{'div'}{'div'}{'div'}[1]...
I want to replace {'div'}{'div'}{'div'}[1] by something else.
So I tried
%s/{'div'}{'div'}{'div'}[1]/by something else/gc
The strings were not found. I though I had to escape the {,},[ and ]
Still string not found.
So I tried to search a single { and it found them.
Then I tried to search {'div'}{'div'}{'div'} and it found it again.
Then {'div'}{'div'}{'div'}[1 was still found.
To find {'div'}{'div'}{'div'}[1]
I had to use %s/{'div'}{'div'}{'div'}[1\]
Why ?
vim 7.3 on Linux
The [] are used in regular expressions to wrap a range of acceptable characters.
When both are supplied unescaped, vim is treating the search string as a regex.
So when you leave it out, or escape the final character, vim cannot interpret a single bracket in a regex context, so does a literal search (basically the best it can do given the search string).
Personally, I would escape the opening and closing square brace to ensure that the meaning is clear.
That's because the [ and ] characters are used to build the search pattern.
See :h pattern and use the help file pattern.txt to try the following experiment:
Searching for the "[9-0]" pattern (without quotes) using /[0-9] will match every digit from 0 to 9 individually (see :h \[)
Now, if you try /\[0-9] or /[0-9\] you will match the whole pattern: a zero, an hyphen and a nine inside square brackets. That's because when you escape one of [ or ] the operator [*] ceases to exist.
Using your search pattern, /{'div'}{'div'}{'div'}[1\] and /{'div'}{'div'}{'div'}\[1] should match the same pattern which is the one you want, while /{'div'}{'div'}{'div'}[1] matches the string {'div'}{'div'}{'div'}1.
In order to avoid being caught by these special characters in regular expressions, you can try using the very magic flag.
E.g.:
:%s/\V{'div'}[1]/replacement/
Notice the \V flag at the beginning of the line.
Because the square brackets mean that vim thinks you're looking for any of the characters inside. This is known as a 'character class'. By escaping either of the square brackets it lets vim know that you're looking for the literal square string ending with '[1]'.
Ideally you should write your expression as:
%s/{'div'}{'div'}{'div'}\[1\]/replacement string/
to ensure that the meaning is completely clear.

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