Regular Expressions 101

Explanation
Pro

^start of line

Character Class[a-zA-Z\d-]{1,100}

{1,100}matches between 1 and 100 characters from the set below:

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

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

\da digit

-the literal - (45₁₀ / 55₈ / 2D₁₆)

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

^[a-zA-Z\d-]{1,100}

RE-1234-56-789-0
123-AB-12-INV
123456789
ABCDE
2019-01-19-ABCD

RE-1234-56-789-0
123-AB-12-INV
123456789
ABCDE
2019-01-19-ABCD