Regular Expressions 101

1st Alternative<!DOCTYPE html>

<!DOCTYPE html>the literal text <!DOCTYPE html> (case sensitive)

2nd Alternative</?\s*[a-z-][^>]*\s*>

<the literal < (60₁₀ / 74₈ / 3C₁₆)

/?optionally matches the literal / (47₁₀ / 57₈ / 2F₁₆)

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

Character Class[a-z-]

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Negated Character Class[^>]*

*matches any number of characters outside the set below:

>the literal > (62₁₀ / 76₈ / 3E₁₆)

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

>the literal > (62₁₀ / 76₈ / 3E₁₆)

3rd Alternative(\&(?:[\w\d]+|#\d+|#x[a-f\d]+);)

Group 1(\&(?:[\w\d]+|#\d+|#x[a-f\d]+);)

\&the literal & (38₁₀ / 46₈ / 26₁₆)

Non-Capturing Group(?:[\w\d]+|#\d+|#x[a-f\d]+)

1st Alternative[\w\d]+

Character Class[\w\d]+

+matches at least one character from the set below:

\wa Unicode word character

\da Unicode decimal digit

2nd Alternative#\d+

#the literal # (35₁₀ / 43₈ / 23₁₆)

\d+a Unicode decimal digit, repeated at least once

3rd Alternative#x[a-f\d]+

#xthe literal text #x (case sensitive)

Character Class[a-f\d]+

+matches at least one character from the set below:

a-fone character from a (97₁₀) to f (102₁₀) (case sensitive)

\da Unicode decimal digit

;the literal ; (59₁₀ / 73₈ / 3B₁₆)

Global pattern flags

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

No unit tests · Add a test to get started

25 tokens

Regular Expression

<!DOCTYPE html>|</?\s*[a-z-][^>]*\s*>|(\&(?:[\w\d]+|#\d+|#x[a-f\d]+);)

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