Regular Expressions 101

Group 1(^[A-Za-z]|(?<=[^\w])[A-Za-z]|(?<![A-Z])[A-Z])

1st Alternative^[A-Za-z]

^start of string

Character Class[A-Za-z]

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

2nd Alternative(?<=[^\w])[A-Za-z]

Positive Lookbehind(?<=[^\w])

Negated Character Class[^\w]

\wa Unicode word character

Character Class[A-Za-z]

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

3rd Alternative(?<![A-Z])[A-Z]

Negative Lookbehind(?<![A-Z])

Character Class[A-Z]

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

Character Class[A-Z]

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

(^[A-Za-z]|(?<=[^\w])[A-Za-z]|(?<![A-Z])[A-Z])

New

PHP: Hypertext Preprocessor
Portable Network Graphics
Ruby on Rails
HyperText Markup Language
First In, First Out
Complementary metal-oxide semiconductor

Regular Expression

Extraction