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Regular Expressions: Inspecting a Regex

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Given a regex, you can inspect its properties:

  • source the pattern string
  • multiline true with the m flag
  • global true with the g flag
  • ignoreCase true with the i flag
  • lastIndex
/^(\w{3})$/i.source     //"^(\\w{3})$"
/^(\w{3})$/i.multiline  //false
/^(\w{3})$/i.lastIndex  //0
/^(\w{3})$/i.ignoreCase //true
/^(\w{3})$/i.global     //false

Lessons in this unit:

0: Introduction
1: Introduction
2: Anchoring
3: Match Items in Ranges
4: Matching a Range Item Multiple Times
5: Negating a Pattern
6: Meta Characters
7: Regular Expressions Choices
8: Quantifiers
9: Optional Items
10: Groups
11: Capturing Groups
12: Using match and exec Without Groups
13: Noncapturing Groups
14: Flags
15: ▶︎ Inspecting a Regex
16: Escaping
17: String Boundaries
18: Replacing
19: Greediness
20: Lookaheads
21: Lookbehinds
22: Unicode
23: Unicode Property Escapes
24: Examples