My point is that I think many developers see it as hard/complex to understand and use regular expressions, but by getting the basic thinking right I believe it is really easy to getting started to use this powerful tool. The presentations was supposed to be a kick start. Note! This presentations is not supposed to stand alone, it is done to support my talk.

1. Thinking regular expression is your way to get started to use regular expressions

2. Mönster sökning vad är regex.

3. Validering

4. NOTIS: 12345 , the bugg x

5. 2008-02-21 2008 /03 / 22 20080423 2008 05 24

6. 21-02-2008 22-03-2008 23-04-2008 24-05-2008

7. 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[ ]))*&quot;(?:(?:)?[ ])*)*:(?:(?:)?[ ])*(§?:(?:(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|&quot;(?:[^amp;quot;]| .|(?:(?:)?[ ]))*&quot;(?:(?:)?[ ])*)(?:(?:(?:)?[ ])*(?:[^()<> @,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|&quot; (?:[^amp;quot;]|.|(?:(?:)?[ ]))*&quot;(?:(?:)?[ ])*))*@(?:(?:)?[ ] )*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;: &quot;.]))|([^]|.)*(?:(?:)?[ ])*)(?:(?:(?:)?[ ])*(? :[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;. ]))|([^]|.)*(?:(?:)?[ ])*))*|(?:[^()<>@,;:&quot;. 00- 31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|&quot;(?:[^amp;quot;]|.|( ?:(?:)?[ ]))*&quot;(?:(?:)?[ ])*)*lt;(?:(?:)?[ ])*(?:@(?:[^()<>@,; :&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|([ ^]|.)*(?:(?:)?[ ])*)(?:(?:(?:)?[ ])*(?:[^()<>@,;:&quot; . 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|([^]]|.)*(?:(?:)?[ ])*))*(?:,@(?:(?:)?[ ])*(?:[^()<>@,;:&quot;.[ 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|([^r]|.)*(?:(?:)?[ ])*)(?:(?:(?:)?[ ])*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|([^] |.)*(?:(?:)?[ ])*))*)*:(?:(?:)?[ ])*)?(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|&quot;(?:[^amp;quot;]| .|(?:(?:)?[ ]))*&quot;(?:(?:)?[ ])*)(?:(?:(?:)?[ ])*(?:[^()<>@, ;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|&quot;(? :[^amp;quot;]|.|(?:(?:)?[ ]))*&quot;(?:(?:)?[ ])*))*@(?:(?:)?[ ])* (?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;. ]))|([^]|.)*(?:(?:)?[ ])*)(?:(?:(?:)?[ ])*(?:[ ^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;. ]))|([^]|.)*(?:(?:)?[ ])*))*gt;(?:(?:)?[ ])*)(?:,*( ?:(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;: &quot;.]))|&quot;(?:[^amp;quot;]|.|(?:(?:)?[ ]))*&quot;(?:(?:)?[ ])*)(?:(?:( ?:)?[ ])*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[ &quot;()<>@,;:&quot;.]))|&quot;(?:[^amp;quot;]|.|(?:(?:)?[ ]))*&quot;(?:(?:)?[ ])*))*@(?:(?:)?[ ])*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]))|([^]|.)*(?:(?:)?[ ])*)(? :(?:(?:)?[ ])*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+| |(?=[&quot;()<>@,;:&quot;.]))|([^]|.)*(?:(?:)?[ ])*))*|(?: [^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;.]]))|&quot;(?:[^amp;quot;]|.|(?:(?:)?[ ]))*&quot;(?:(?:)?[ ])*)*lt;(?:(?:) ?[ ])*(?:@(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot; ()<>@,;:&quot;.]))|([^]|.)*(?:(?:)?[ ])*)(?:(?:(?:) ?[ ])*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<> @,;:&quot;.]))|([^]|.)*(?:(?:)?[ ])*))*(?:,@(?:(?:)?[ ])*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@, ;:&quot;.]))|([^]|.)*(?:(?:)?[ ])*)(?:(?:(?:)?[ ] )*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;: &quot;.]))|([^]|.)*(?:(?:)?[ ])*))*)*:(?:(?:)?[ ])*)? (?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[&quot;()<>@,;:&quot;. ]))|&quot;(?:[^amp;quot;]|.|(?:(?:)?[ ]))*&quot;(?:(?:)?[ ])*)(?:(?:(?: )?[ ])*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+||(?=[ &quot;()<>@,;:&quot;.]))|&quot;(?:[^amp;quot;]|.|(?:(?:)?[ ]))*&quot;(?:(?:)?[ ]) *))*@(?:(?:)?[ ])*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ]) +||(?=[&quot;()<>@,;:&quot;.]))|([^]|.)*(?:(?:)?[ ])*)(?:.(?:(?:)?[ ])*(?:[^()<>@,;:&quot;. 00-31]+(?:(?:(?:)?[ ])+| |(?=[&quot;()<>@,;:&quot;.]))|([^]|.)*(?:(?:)?[ ])*))*gt;(?:( ?:)?[ ])*))*)?;*)

11. ^

12. $

13. ^grey

14. ^ grey

15. ^ g rey

16. ^g r ey

17. ^gr e y

18. ^gre y

19. ^grey$

21. / /Everybody get in front/ You know regular expressions

23. [ea] Character Classes

24. [1234] Character Classes

25. [1-4] Character Classes

26. [^1-4] Character Classes

27. . Any Character

28. + Repetition

29. * Repetition

30. Shortcut [0-9]

31. Shortcut [^0-9]

32. () Backreference

33. .+[?] Questions