Let's say I have the text a123456. I want a string of b123456 to match. So essentially, 'match if all characters are the same except for the first character'. Am I asking for the impossible with regex?
Use the dot (.) to match any character. So, a possible Regex would be:
/^.123456$/
If you want to use zero length assertion with regex, you can have lookbehind approach in following way :
(?<=\w)your_value$ // your_value should be text which you want to check
I think you can figure it out on your own. This ain't tough, just needs some understanding between you and Regex. Why don't you go through the following links and try to make a regex on your own.
https://www.talentcookie.com/2015/07/regular-expressions/
https://www.talentcookie.com/2015/07/lets-practice-regular-expression/
https://www.talentcookie.com/2016/01/some-useful-regular-expression-terminologies/
Related
I'm trying to filter words which is not in the "[ ]".
Why is this not working?
[^\[][\u0000-\u024F]+[^\]]
The reason your expression is not working is that it matches all text inside brackets as well as outside.
This is the best I've been able to do:
/(?:^|])[^[]+/g
It includes the ]s in the match because look-behind is not allowed:
http://regexr.com/3c515
If look-behind were allowed, this would be the ticket:
/(?:^|(?<=]))[^[]+/g
https://regex101.com/r/lK9tS7/3
Because this will match [\u0000-\u024F]+ and 2 character which will be matches by [^\[]. If you want to your regex engine match the whole of pattern you need to use start and end anchors in your regex :
/^[^\[][\u0000-\u024F]+[^\]]$/m
But this will work if your string is contain words in each line, which is not a proper way.
As a better way you can use negative look arounds :
(?<!\[)[\u0000-\u024F]+(?!\])
Hy,
please help me with a Regex to find phrases in a text.
My Regex is not ok. My assumption that phrases begin with uppercase and end with an dot, and between can contain anything.
\b([A-Z]+[aA-zZ]*\b(.)+)
Sincerly,
You can use the following if your between phrase doesn't also consist of a dot.
[A-Z][^.]*\.
Or perhaps, you could try using the following.
[A-Z].*?\.
Here is one variant
\b([A-Z][^.]*\.+)\b
Try this, it starts with a Capital letter, end with a dot, zero or more anything in between them:
^[A-Z].*[.]$
i have a problem here, i have the following string
#Novriiiiii yauda busana muslim #nencor haha. wa'alaikumsalam noperi☺
then i use this regex pattern to select all the string
\w+
however, i need to to select all the string except the word which prefixed with # like #Novriiiiii or #nencor which means, we have to exclude the #word ones
how do i do that ?
ps. i am using regexpal to compile the regex. and i want to apply the regex pattern into yahoo pipes regex. thank you
You can use a negative lookbehind so that if a word is preceded by # it is excluded. You also need a word boundary before the word or else the lookbehind will only affect the first character.
(?<!#)\b\w+
http://rubular.com/r/ONEl70Am5Q
Does this suit your needs?
http://rubular.com/r/uuXvNrUiGJ
[^#\w+]\w+
This would sole your problem indeed:
[^#\w+][\w.]+
Check this link: http://regexr.com?34tq7
If you cannot use a negative lookbehind as other answers have already suggested, here's a workaround.
\w already doesn't match the # character, so you'd want something like this:
[^#]\w+
But this will (a) not work at the beginning of the string, and (b) include the character before the word in the match. To fix (a), we can do:
(^|[^#])\w+
To fix (b), we parenthesize the part we want:
(^|[^#])(\w+)
Then use $2 or \2 (depending on regex dialect) to refer to the matched word.
Another option is to include the # symbol in the word:
[\w#]+
And then add another step in your Pipe to filter out all words that start with an #.
A way to do that is to remove words that you don't want. Example:
find: #\w+
replace: empty string
you obtain the text without #abcdef words.
I'm very new at regex, and to be completely honest it confounds me. I need to grab the string after a certain character is reached in said string. I figured the easiest way to do this would be using regex, however like I said I'm very new to it. Can anyone help me with this or point me in the right direction?
For instance:
I need to check the string "23444:thisstring" and save "thisstring" to a new string.
If this is your string:
I'm very new at regex, and to be completely honest it confounds me
and you want to grab everything after the first "c", then this regular expression will work:
/c(.*)/s
It will return this match in the first matched group:
"ompletely honest it confounds me"
Try it at the regex tester here: regex tester
Explanation:
The c is the character you are looking for
.* (in combination with /s) matches everything left
(.*) captures what .* matched, making it available in $1 and returned in list context.
Regex for deleting characters before a certain character!
You can use lookahead like this
.*(?=x)
where x is a particular character or word or string.{using characters like .,$,^,*,+ have special meaning in regex so don't forget to escape when using it within x}
EDIT
for your sample string it would be
.*(?=thisstring)
.* matches 0 to many characters till thisisstring
Here is a one-line solution for matching everything after "before"
print $1."\n" if "beforeafter" =~ m/before(.*)/;
Edit:
While using lookbehind is possible, it's not required. Grouping provides an easier solution.
To get the string before : in your example, you have to use [^:][^:]*:\(.*\). Notice that you should have at least one [^:] followed by any number of [^:]s followed by an actual :, the character you are searching for.
I search for a regex pattern, which shouldn't match a group but everything else.
Following regex pattern works basicly:
index\.php\?page=(?:.*)&tagID=([0-9]+)$
But the .* should not match TaggedObjects.
Thanks for any advices.
(?:.*) is unnecessary - you're not grouping anything, so .* means exactly the same. But that's not the answer to your question.
To match any string that does not contain another predefined string (say TaggedObjects), use
(?:(?!TaggedObjects).)*
In your example,
index\.php\?page=(?:(?!TaggedObjects).)*&tagID=([0-9]+)$
will match
index.php?page=blahblah&tagID=1234
and will not match
index.php?page=blahTaggedObjectsblah&tagID=1234
If you do want to allow that match and only exclude the exact string TaggedObjects, then use
index\.php\?page=(?!TaggedObjects&tagID=([0-9]+)$).*&tagID=([0-9]+)$
Try this. I think you mean you want to fail the match if the string contains an occurence of 'TaggedObjects'
index\.php\?page=(?!.*TaggedObjects).*&tagID=([0-9]+)$