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• Regular Expression to get the size value of a CSS property?

  - by thiesdiggity

  I wrote a regular expression to get the size from a CSS property: /(([+-]?\d*\.?\d+(\s)*(px|em|ex|pt|in|pc|mm|cm)?)|thin|medium|thick)(\s|;|$)/i but for some reason its not working as intended. For example, when I run the following: preg_match_all('/(([+-]?\d*\.?\d+(\s)*(px|em|ex|pt|in|pc|mm|cm)?)|thin|medium|thick)(\s|;|$)/i', "border-bottom:1px solid #99999;", $matches); It outputs: 1px 99999; But I only want the 1px value returned. I understand why its returning the above but can't seem to figure out how to only return the size and not the color value. I tried using the following negative lookbehind but it's not working either: /(((?<!#\d{3}|#\d{6})[+-]?\d*\.?\d+(\s)*(px|em|ex|pt|in|pc|mm|cm)?)|thin|medium|thick)(\s|;|$)/i I want to use preg_match_all for those CSS properties that can have multiple size values (i.e. margin). Anyone have any ideas how to get this regex to return only the size values? Thanks for your help!

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• codingBat repeatEnd using regex

  - by polygenelubricants

  I'm trying to understand regex as much as I can, so I came up with this regex-based solution to codingbat.com repeatEnd: Given a string and an int N, return a string made of N repetitions of the last N characters of the string. You may assume that N is between 0 and the length of the string, inclusive. public String repeatEnd(String str, int N) { return str.replaceAll( ".(?!.{N})(?=.*(?<=(.{N})))|." .replace("N", Integer.toString(N)), "$1" ); } Explanation on its parts: .(?!.{N}): asserts that the matched character is one of the last N characters, by making sure that there aren't N characters following it. (?=.*(?<=(.{N}))): in which case, use lookforward to first go all the way to the end of the string, then a nested lookbehind to capture the last N characters into \1. Note that this assertion will always be true. |.: if the first assertion failed (i.e. there are at least N characters ahead) then match the character anyway; \1 would be empty. In either case, a character is always matched; replace it with \1. My questions are: Is this technique of nested assertions valid? (i.e. looking behind during a lookahead?) Is there a simpler regex-based solution?

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• javascript regex: replace url text link with image,but not in html tags

  Hi this is my pice of code: <div style="overflow: hidden; width: 445px;">[IMG]http://i29.tinypic.com/mydog.png[/IMG] tak si to http://i29.tinypic.com/mycat.png Lorem ipsum loremai <img width="15" border="0" align="middle" src="images/smejo.gif" valign="middle"/> <img src=http://www.example.com/index.png alt> <img src="http://www.example.com/index.png" alt>     <a href="#reakcia" title="reagovat na temu"><span class="poradna-tl-reaguj"><reaction> </span></a></div> </td> </tr><img src=http://www.example.com/index.png alt><img src="http://www.example.com/index.png" alt> and i need regex pattern to replace ONLY text image links with image without touch of inner url tags. But i can't use "Lookbehind" or possessive quantifiers because JS don't support them=/ So i want to catch only "http://i29.tinypic.com/mydog.png" and "http://i29.tinypic.com/mycat.png". I using array method to replacing (will be greasemonkey script.) Many Thanks

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• Selectively search and replace certain lines using a regular expression

  - by eneveu

  I have a file containing a lot of SQL statements, such as: CREATE TABLE "USER" ( "ID" INTEGER PRIMARY KEY, "NAME" CHARACTER VARYING(50) NOT NULL, "AGE" INTEGER NOT NULL ); COPY "USER" (id, name, age) FROM stdin; 1 Skywalker 19 2 Kenobi 57 I want the column names in the COPY statements to be uppercased and quoted: COPY "USER" ("ID", "NAME", "AGE") FROM stdin; Using sed, I found the following regexp: sed -r 's/([( ])(\w+)([,)])/\1"\U\2\E"\3/g' It does replace the column names, but it is not selective enough, and replaces other words in the file: ~/test]$sed -r 's/([( ])(\w+)([,)])/\1"\U\2\E"\3/g' star_wars_example CREATE TABLE "USER" ( "ID" INTEGER PRIMARY "KEY", "NAME" CHARACTER VARYING("50")NOT "NULL", "AGE" INTEGER NOT NULL ); COPY "USER" ("ID", "NAME", "AGE") FROM stdin; 1 Skywalker 19 2 Kenobi 57 To avoid this problem, I want sed to only apply my regexp to the lines starting with COPY and ending with FROM stdin;. I have looked into lookahead / lookbehind, but they are not supported in sed. They seem to be supported in super-sed, but I am currently using Cygwin (Windows is mandatory here...) and it does not seem available in the package list. Is there a way to force sed to only consider specific line? I've considered piping my file through grep before applying sed, but other lines will then disappear from the output. Am I missing something obvious? It would be great if the answer was easily applicable on a default Cygwin install. I guess I could try installing super-sed on cygwin, but I'd like to know if there are more obvious ideas

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• PHP Regex: How to match anything except a pattern between two tags

  - by Ryan

  Hello, I am attempting to match a string which is composed of HTML. Basically it is an image gallery so there is a lot of similarity in the string. There are a lot of <dl> tags in the string, but I am looking to match the last <dl>(.?)+</dl> combo that comes before a </div>. The way I've devised to do this is to make sure that there aren't any <dl's inside the <dl></dl> combo I'm matching. I don't care what else is there, including other tags and line breaks. I decided I had to do it with regular expressions because I can't predict how long this substring will be or anything that's inside it. Here is my current regex that only returns me an array with two NULL indicies: preg_match_all('/<dl((?!<dl).)+<\/dl>(?=<\/div>)/', $foo, $bar) As you can see I use negative lookahead to try and see if there is another <dl> within this one. I've also tried negative lookbehind here with the same results. I've also tried using +? instead of just + to no avail. Keep in mind that there's no pattern <dl><dl></dl> or anything, but that my regex is either matching the first <dl> and the last </dl> or nothing at all. Now I realize . won't match line breaks but I've tried anything I could imagine there and it still either provides me with the NULL indicies or nearly the whole string (from the very first occurance of <dl to </dl></div>, which includes several other occurances of <dl>, exactly what I didn't want). I honestly don't know what I'm doing incorrectly. Thanks for your help! I've spent over an hour just trying to straighten out this one problem and it's about driven me to pulling my hair out.

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