The key to getting this to work is to tell sed to exclude what you don’t want to be output as well as specifying what you do want. This technique depends on knowing how many matches you’re looking for. The grep command below works for an unspecified number of matches. string=’This is a sample 123 … Read more
Use the grepl function grepl( needle, haystack, fixed = TRUE) like so: grepl(value, chars, fixed = TRUE) # TRUE Use ?grepl to find out more.
Currently, UUID’s are as specified in RFC4122. An often neglected edge case is the NIL UUID, noted here. The following regex takes this into account and will return a match for a NIL UUID. See below for a UUID which only accepts non-NIL UUIDs. Both of these solutions are for versions 1 to 5 (see … Read more
Sorry for reactivating this question, but I didn’t find the right answer here. In formatting numbers you can use 0 as a mandatory place and # as an optional place. So: // just two decimal places String.Format(“{0:0.##}”, 123.4567); // “123.46” String.Format(“{0:0.##}”, 123.4); // “123.4” String.Format(“{0:0.##}”, 123.0); // “123” You can also combine 0 with #. … Read more
This can be done without regex: >>> string = “Special $#! characters spaces 888323″ >>> ”.join(e for e in string if e.isalnum()) ‘Specialcharactersspaces888323’ You can use str.isalnum: S.isalnum() -> bool Return True if all characters in S are alphanumeric and there is at least one character in S, False otherwise. If you insist on using … Read more
^[^<>]+$ The caret in the character class ([^) means match anything but, so this means, beginning of string, then one or more of anything except < and >, then the end of the string.
Given a regular expression of (foobar) you can reference the first group using $1 and so on if you have more groups in the replace input field.
I want to add this answer for quickreference. Feel free to update. .NET Regex using balancing groups. \((?>\((?<c>)|[^()]+|\)(?<-c>))*(?(c)(?!))\) Where c is used as the depth counter. Demo at Regexstorm.com Stack Overflow: Using RegEx to balance match parenthesis Wes’ Puzzling Blog: Matching Balanced Constructs with .NET Regular Expressions Greg Reinacker’s Weblog: Nested Constructs in Regular Expressions … Read more
find . -regextype sed -regex “.*/[a-f0-9\-]\{36\}\.jpg” Note that you need to specify .*/ in the beginning because find matches the whole path. Example: susam@nifty:~/so$ find . -name “*.jpg” ./foo-111.jpg ./test/81397018-b84a-11e0-9d2a-001b77dc0bed.jpg ./81397018-b84a-11e0-9d2a-001b77dc0bed.jpg susam@nifty:~/so$ susam@nifty:~/so$ find . -regextype sed -regex “.*/[a-f0-9\-]\{36\}\.jpg” ./test/81397018-b84a-11e0-9d2a-001b77dc0bed.jpg ./81397018-b84a-11e0-9d2a-001b77dc0bed.jpg My version of find: $ find –version find (GNU findutils) 4.4.2 Copyright (C) 2007 … Read more
Use the RegExp object constructor to create a regular expression from a string: var re = new RegExp(“a|b”, “i”); // same as var re = /a|b/i;