Regular Expressions 101

^start of line

Wthe literal W (87₁₀ / 127₈ / 57₁₆) (case sensitive)

\d{0,3}a digit, repeated between 0 and 3 times

Character Class[A-Z]?

?matches at most one character from the set below:

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

$end of line

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

^W\d{0,3}[A-Z]?$

New

W
W1
W12
W123
W123A

-- casos inválidos (tem que ter exatamente 3 dígitos antes do X, a regex não deveria pegar esses casos)
W1X
W12X