Regex - How do you match everything except four digits in a row?

Question

Using Regex, how do you match everything except four digits in a row? Here is a sample text that I might be using:

foo1234bar
baz      1111bat
asdf 0000 fdsa
a123b

Matches might look something like the following:

"foo", "bar", "baz      ", "bat", "asdf ", " fdsa", "a123b"

Here are some regular expressions I've come up with on my own that have failed to capture everything I need:

[^\d]+            (this one includes a123b)
^.*(?=[\d]{4})    (this one does not include the line after the 4 digits)
^.*(?=[\d]{4}).*  (this one includes the numbers)

Any ideas on how to get matches before and after a four digit sequence?

Answer 1

You haven't specified your app language, but practically every app language has a split function, and you'll get what you want if you split on \\d{4} .

eg in java:

String[] stuffToKeep = input.split("\\d{4}");

Answer 2

You can use a negative lookahead:

(?!\b\d{4}\b)(\b\w+\b)

Demo

Answer 3

In Python the following is very close to what you want:

In [1]: import re

In [2]: sample = '''foo1234bar
   ...: baz      1111bat
   ...: asdf 0000 fdsa
   ...: a123b'''

In [3]: re.findall(r"([^\d\n]+\d{0,3}[^\d\n]+)", sample)
Out[3]: ['foo', 'bar', 'baz      ', 'bat', 'asdf ', ' fdsa', 'a123b']