Matching words except those in tags with regex

[Bob Homes]

Hello,

To begin, I'm not even sure regex is the best tool for this. I want to do a replace all match of all occurrences of a word, except when it occurs between < and >. I found out to use the /b for word boundry matches so it only replaces full word matches, but trying to find only those outside tags is difficult. I tried to implement some sort of lookahead and look behind scheme but it failed.

So if the string is "<Hello There World>Hello There World", and I want to replace "There" with "bob"; the final string would be "<Hello There World>Hello bob World"

Is there a simple way to do this?

[Henry Wong]

To begin, I'm not even sure regex is the best tool for this.

It is probably not -- but it is doable. For one level tags -- no nesting, is should be straight forward. For two levels, it is still doable. For three or more levels, it gets even harder, and is probably not worth it.

I tried to implement some sort of lookahead and look behind scheme but it failed.

For one level, lookahead should work. Just search for the word, followed by a lookahead of anything but the close tag (zero or more), followed by (still part of lookahead) either the open tag, or end of input.

Henry

[Bob Homes]

Here is what I tried, hopefully per your instructions:

    
		String s = "<hello world lo hel>hello world lo hel";
		s = s.replaceAll("\\blo\\b(?!>(<|\\z))", "bob");
		System.out.println(s);

Expected output is <hello world lo hel>hello world bob hel
Actual output is <hello world bob hel> hello world bob hel

Most likely it is my regex syntax. I had never heard of look ahead and look behind until earlier today.

[Henry Wong]

s = s.replaceAll("\\blo\\b(?=[^>]*?(<|$))", "bob");