Regular Expressions 101

Pro

\ba Unicode word boundary

Group digit(?P<digit>\d{4})

\d{4}a Unicode decimal digit, repeated exactly 4 times

Non-Capturing Group(?: (?P<addition>[A-Z]{2}))?

?repeats the group contents below at most once:

the literal (32₁₀ / 40₈ / 20₁₆)

Group addition(?P<addition>[A-Z]{2})

Character Class[A-Z]{2}

{2}matches exactly 2 characters from the set below:

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

the literal (32₁₀ / 40₈ / 20₁₆)

Group city(?P<city>\S.*)

\Sany character that is not Unicode whitespace

.*any Unicode 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.

25 tokens

\b(?P<digit>\d{4})(?: (?P<addition>[A-Z]{2}))? (?P<city>\S.*)

New

1234 AA

5523 ZB

1234 AA Amsterdam

1234 Amsterdam

5555 AD 's-Hertogenbosch

2244 's-Gravenzande

1234 AA

5523 ZB

1234 AA Amsterdam

1234 Amsterdam

5555 AD 's-Hertogenbosch

2244 's-Gravenzande