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GeezerVison is showing regexone.com — RegexOne - Learn Regular Expressions - Problem X: Infinity and beyond!

RegexOne
Learn Regular Expressions with simple, interactive exercises.

Interactive Tutorial

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All Lessons

Lesson 1: An Introduction, and the ABCs Lesson 1½: The 123s Lesson 2: The Dot Lesson 3: Matching specific characters Lesson 4: Excluding specific characters Lesson 5: Character ranges Lesson 6: Catching some zzz's Lesson 7: Mr. Kleene, Mr. Kleene Lesson 8: Characters optional Lesson 9: All this whitespace Lesson 10: Starting and ending Lesson 11: Match groups Lesson 12: Nested groups Lesson 13: More group work Lesson 14: It's all conditional Lesson 15: Other special characters Lesson X: Infinity and beyond!

Practice Problems

Problem 1: Matching a decimal numbers Problem 2: Matching phone numbers Problem 3: Matching emails Problem 4: Matching HTML Problem 5: Matching specific filenames Problem 6: Trimming whitespace from start and end of line Problem 7: Extracting information from a log file Problem 8: Parsing and extracting data from a URL Problem X: Infinity and beyond!

Language Guides

C# Javascript Java PHP Python

Problem X: Infinity and beyond!

Congrats on getting through all the problems! To learn how to use regular expressions in some common programming languages, continue on to the references in the menu in the header above. Otherwise, we hope you can start applying regular expressions in your day to day work!

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