Chapter 4: Advanced Patterns

1. 4.1 - Positive Lookahead
2. 4.2 - Negative Lookahead
3. 4.3 - Atomic Groups

4.1 - Positive Lookahead

Use \d+ for positive lookahead.

1. 1.1 - Simple Match
2. 1.2 - Grouping

4.2 - Negative Lookahead

Use \d+ for negative lookahead.

1. 2.1 - Simple Match
2. 2.2 - Grouping

4.3 - Atomic Groups

Use (?:) for atomic groups.

1. 3.1 - Simple Match
2. 3.2 - Grouping