Regular Expressions 101

Pro

^start of line

Negative Lookahead(?!.*\b(?:dirty|rotten)\b)

.*any character (except for line terminators), repeated any number of times

\ban ASCII word boundary

Non-Capturing Group(?:dirty|rotten)

1st Alternativedirty

dirtythe literal text dirty (case sensitive)

2nd Alternativerotten

rottenthe literal text rotten (case sensitive)

\ban ASCII word boundary

Non-Capturing Group(?:(?!(?:apple|peach|pear)).)*

*repeats the group contents below any number of times:

Negative Lookahead(?!(?:apple|peach|pear))

Non-Capturing Group(?:apple|peach|pear)

1st Alternativeapple

applethe literal text apple (case sensitive)

2nd Alternativepeach

peachthe literal text peach (case sensitive)

3rd Alternativepear

pearthe literal text pear (case sensitive)

.any character (except for line terminators)

Non-Capturing Group(?:red|green|yellow)

1st Alternativered

redthe literal text red (case sensitive)

2nd Alternativegreen

greenthe literal text green (case sensitive)

3rd Alternativeyellow

yellowthe literal text yellow (case sensitive)

\ban ASCII word boundary

.*any character (except for line terminators), repeated any number of times

\ban ASCII word boundary

Non-Capturing Group(?:apple|peach|pear)

1st Alternativeapple

applethe literal text apple (case sensitive)

2nd Alternativepeach

peachthe literal text peach (case sensitive)

3rd Alternativepear

pearthe literal text pear (case sensitive)

\ban ASCII word boundary

.*any character (except for line terminators), repeated any number of times

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

^(?!.*\b(?:dirty|rotten)\b)(?:(?!(?:apple|peach|pear)).)*(?:red|green|yellow)\b.*\b(?:apple|peach|pear)\b.*$

New

 I have an green apple I have a yellow peach I have red and green apples

I have a dirty red apple I have a green peach that is dirty I have a yellow dirty apple

This is a green pear
This is a rotten green pear

This is pear, a green pear