Regular Expressions 101

Positive Lookbehind(?<=https:\/\/letterboxd\.com\/)

https:the literal text https: (case sensitive)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

letterboxdthe literal text letterboxd (case sensitive)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

comthe literal text com (case sensitive)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

Character Class[0-9a-z-_]*

*matches any number of characters from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

Positive Lookahead(?=film\/.*)

filmthe literal text film (case sensitive)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

.*any character (except for line terminators), 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.

Search reference

Regular Expression

(?<=https:\/\/letterboxd\.com\/)[0-9a-z-_]*\/(?=film\/.*)

Test String
New

https://letterboxd.com/user_name/film/pokemon-the-movie-secrets-of-the-jungle/
https://letterboxd.com/user-name/film/pokemon-the-movie-secrets-of-the-jungle/
https://letterboxd.com/username/film/pokemon-the-movie-secrets-of-the-jungle/
https://letterboxd.com/user_name56/film/pokemon-the-movie-secrets-of-the-jungle/

Regular Expression

Test StringNew

SubstitutionProcessing...

Test String
New

Substitution
Processing...