Regular Expressions 101

Pro

1st Alternative(?<=CHEM|HIST)\s*

Positive Lookbehind(?<=CHEM|HIST)

1st AlternativeCHEM

CHEMthe literal text CHEM (case sensitive)

2nd AlternativeHIST

HISTthe literal text HIST (case sensitive)

\s*a Unicode whitespace character, repeated any number of times

2nd Alternative(?<=MATHS)\s*

Positive Lookbehind(?<=MATHS)

MATHSthe literal text MATHS (case sensitive)

\s*a Unicode whitespace character, repeated any number of times

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.

25 tokens

Regular Expression

(?<=CHEM|HIST)\s*|(?<=MATHS)\s*

New

CLASS 8B CHEM 	| MON | 10AM to 10:40AM
--Rescheduled-- CLASS 8B MATHS  | MON | 11AM to 11:40AM
CLASS 8B HIST  | MON | 5PM to 5:40PM'
CLASS 8B CHEM 	| MON | 10AM to 10:40AM

Extraction

CLASS 8B CHEM 	| MON | 10AM to 10:40AM
--Rescheduled-- CLASS 8B MATHS  | MON | 11AM to 11:40AM
CLASS 8B HIST  | MON | 5PM to 5:40PM'
CLASS 8B CHEM 	| MON | 10AM to 10:40AM