Regex to upper case not surrounded by single quotes

Question

hello 'this' is my'str'ing

If I have string like this, I'd like to make it all upper case if not surrounded by single quote.

hello 'this' is my'str'ing=>HELLO 'this' IS MY'str'ING

Is there a easy way I can achieve this in node perhaps using regex?

Maybe you're looking for http://stackoverflow.com/questions/5166862/javascript-regular-expression-iterator-to-extract-groups — paddy, Mar 07 '17 at 22:58
Match `([^']+)('[^']*')?` then use a _function()_ callback to join the upper of group 1 with group 2. — , Mar 07 '17 at 23:07
@sln Except that that fails on something like `O'Hare 'International' Airport`. — Kenneth K., Mar 07 '17 at 23:16
Possible duplicate of [Alternative to regex: match all instances not inside quotes](http://stackoverflow.com/questions/6462578/alternative-to-regex-match-all-instances-not-inside-quotes) — ssc-hrep3, Mar 07 '17 at 23:34
@ssc-hrep3 It's not a duplicate, quotes don't have the troublesome dual-role that apostrophe's do. — Regular Jo, Mar 08 '17 at 02:21
@KennethK. - I can't read peoples minds for intent. If it's you who needs an answer, validate the regex first in a separate regex `^[^']*(?:'[^']*'[^']*)+[^']*$` — , Mar 09 '17 at 00:29

score 1 · Accepted Answer · edited May 23 '17 at 12:17

You can use the following regular expression:

'[^']+'|(\w)

Here is a live example:

var subject = "hello 'this' is my'str'ing";
var regex = /'[^']+'|(\w)/g;
replaced = subject.replace(regex, function(m, group1) {
    if (!group1) {
        return m;
    }
    else {
        return m.toUpperCase();
    }
});

document.write(replaced);

Credit of this answer goes to zx81. For more information see the original answer of zx81.

Regular Jo · Answer 2 · 2017-03-09T02:58:58.680

Since Javascript doesn't support lookbehinds, we have to use \B which matches anything a word boundary doesn't match.

In this case, \B' makes sure that ' isn't to the right of anything in \w ([a-zA-Z0-9_]). Likewise, '\B does a similar check to the left.

(?:(.*?)(?=\B'.*?'\B)(?:(\B'.*?'\B))|(.*?)$) (regex demo)

Use a callback function and check to see if the length of captures 1 or 3 is > 0 and if it is, return an uppercase on the match

**The sample uses \U and \L just to uppercase and lowercase the related matches. Your callback need not ever effect $2's case, so "Adam" can stay "Adam", etc.

Unrelated, but a note to anyone who might be trying to do this in reverse. it's much easier to the the REVERSE of this:

(\B'.+?'\B) regex demo

Regex to upper case not surrounded by single quotes

2 Answers2