Match two words not having a specific word between them

Question

I need to find all combinations of two words, say from and to, not having a particular word between them, say exclude

from
exclude
to

from
include
to

Only the second from -> to should match. Currently I can do this but just excluding single characters

from([^x]*?)to

you probably want a [lookaround](http://www.regular-expressions.info/lookaround.html) — Marc B, Jul 13 '16 at 16:33
How strictly should the words be matched? Would `excluded` be OK or not? What about `fromage` or `today` - should they count as start/end markers, too? — Tim Pietzcker, Jul 13 '16 at 16:46
Tim I'm looking for exact words match. So they won't be what I'm looking for — Michele, Jul 13 '16 at 17:54

score 1 · Accepted Answer · edited May 23 '17 at 12:08

You need to use a tempered greedy token:

When to Use this Technique
Suppose our boss now tells us that we still want to match up to and including {END}, but that we also need to avoid stepping over a {MID} section, if it exists. Starting with the lazy dot-star version to ensure we match up to the {END} delimiter, we can then temper the dot to ensure it doesn't roll over {MID}:

{START}(?:(?!{MID}).)*?{END}

If more phrases must be avoided, we just add them to our tempered dot:

 {START}(?:(?!{MID})(?!{RESTART}).)*?{END}

This is a useful technique to know about.

Use

from((?:(?!exclude|to|from).)*)to

Use DOTALL modifier if you need the dot to match newlines.

See the regex demo

See a related SO thread about a tempered greedy token.

Match two words not having a specific word between them

1 Answers1