Regular Expressions 101

Pro

Positive Lookahead(?= [a-z]|\.|(?<!\b[A-Z][a-z]*) (?=[A-Z]))

1st Alternative [a-z]

the literal (32₁₀ / 40₈ / 20₁₆)

Character Class[a-z]

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

2nd Alternative\.

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

3rd Alternative(?<!\b[A-Z][a-z]*) (?=[A-Z])

Negative Lookbehind(?<!\b[A-Z][a-z]*)

\ban ASCII word boundary

Character Class[A-Z]

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

Character Class[a-z]*

*matches any number of characters from the set below:

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

the literal (32₁₀ / 40₈ / 20₁₆)

Positive Lookahead(?=[A-Z])

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

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

26 tokens

Regular Expression

(?= [a-z]|\.|(?<!\b[A-Z][a-z]*) (?=[A-Z]))

New

Bangalore railway line of the Indian Railway. It comes under Nagpur division of the Central Railway.
test. Toronto
 test Toronto 
 water Tor Museum wants
Toronto a Museum with

Extraction

Bangalore railway line of the Indian Railway. It comes under Nagpur division of the Central Railway.
test. Toronto
 test Toronto 
 water Tor Museum wants
Toronto a Museum with