REGEX remove spaces or dashes, if they are in between numbers

Question

I'm in the process of modifying an existing regex to match Credit Card numbers. Sometimes such numbers are presented as follows that separate the number chunks with spaces or dashes as follows;

3756-4564-2323-3435
3756 6432 3233 435

These types of matches should be preprocessed to remove those special characters. Usually the number chunks are of 3 to 4 digits.

thanks

Answer 1

In bash you could remove anything that is not numbers with:

$ var="3756-4564-2323-3435"
$ echo "${var//[^0-9]}"
3756456423233435