Merge pull request #8 from lukeaiken/54145821_about_symbols_master

about symbols master

[Delivers #54145821]
Gaining karma by learning about_regular_expressions

* Regexp Class

* Regexp return nil

* Regexp ? means optional

[#54145823]
Gaining karma by learning about_regular_expressions

* Regexp + means one or more

* Regexp * means zero or more

* left most match wins!

* Regexp [] are options for characters

[#54145823]
Gaining karma by learning about_regular_expressions

* Regexp \d is a shortcut for a digital character

* character classes can include ranges

* \s represent white space

Gaining karma by learning about_regular_expressions

* \w represent word

[#54145823]
Gaining karma by learning about_regular_expressions

* . is shortcut for any non-new-line character

* character class can be negated with capitals

Gaining karma by learning about_regular_expressions

* \A anchors to the start of the string

[#54145823]
Gaining karma by learning about_regular_expressions

* \z anchors to the end of the string

* ^ anchors to the start of lines

* $ anchors to the end of lines

Gaining karma by learning about_regular_expressions

* \b anchors to a word boundary

[#54145823]
Gaining karma by learning about_regular_expressions

* parentheses group contents

* parentheses also capture matched content by
  number

* variables can be used to access captures

Gaining karma by learning about_regular_expressions

* vertical pipe means or

[#54145823]
Gaining karma by learning about_regular_expressions

* scan is like find all

* sub can take a regexp

* sub can take a regexp

Gaining karma by learning about_regular_expressions

* gsub can take a regexp

[#54145823]