Regular Expressions

1. 1.What Are Regular Expressions?
2. 2.Literals, the Dot, and the Escape
3. 3.Anchors: Start, End, and Word Boundaries
4. 4.Character Classes and POSIX Classes
5. 5.Quantifiers: How Many Times?
6. 6.Grouping, Alternation, and Backreferences
7. 7.grep and egrep in Depth
8. 8.sed and Regex in Depth
9. 9.Regex in awk
10. 10.Regex in Bash: [[ =~ ]] and BASH_REMATCH
11. 11.PCRE: Lookahead, Lookbehind, and Advanced Features
12. 12.Your Regex Toolkit: Patterns, Testing, and Real Pipelines