Almost every programmer faces regular expressions in everyday practice. Many are frightened by them, but regular expressions are based on few basic ideas, and by understanding them you can learn understand expressions once and forever.
Learn basic regular expressions.
Learn to create and use character classes
Learn how to define boundries
Learn how to alternate between options
Learn how to deal with repetitions
Learn to stop being greedy
Learn how to re-use groups in regular expressions.
Learn how to control the behaviour with flags
Learn to exclude things from the result
Learn to use conditionals
Learn few global flags
Some courses include challenge exercises. They will help you obtain more experience in programming and strengthen new skill. This particular course doesn't have any, but you can check out challenges from other courses.
Co-founder and CTO of Hexlet. One of the organizers of Nastachku.ru conference. In the past — head of undev.ru Ulyanovsk, software developer at Qik (Skype). Creates engineering culture in companies and brings XP, DDD and DevOps. Mental programming evangelist.