Regex

Advanced search syntax. Used for matching information against patterns. Uses:

* Input Validation
* Searching (& replacing)
* Data Scraping
* Syntax Highlighting
* Data Mapping

Syntax:

• / /
  • Delimiters for the regexp
• [ ]
  • used to group a range of acceptable characters
• A-Z and 0-9
  • Sequential characters can be grouped
• Quantifier Characters:
  • ? - match 0 or 1 times (optional)
  • * - match 0 or more times
  • + - match 1 or more times
  • {#}- match an exact # of times
• | -   or
• () - used in conjunction w/ | to designate alternatives

Examples:

<[a-z]+[^>]*\s+{attr}\s*=\s*("[^"]*"|'[^']*'|[^\s >]*)

- used to find html tags with a specific attribute (`{attr}`)