Regular Expressions 101

Explanation
Pro

^start of line

Group 1(https?:/)?

?repeats the group contents below at most once:

httpthe literal text http (case sensitive)

s?optionally matches the literal s (115₁₀ / 163₈ / 73₁₆) (case sensitive)

:/the literal text :/

/the literal / (47₁₀ / 57₈ / 2F₁₆)

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

^(https?:/)?/

foobar
/fooWithSlash
http://foo.com
https://bar.net

foobar
/fooWithSlash
http://foo.com
https://bar.net