Regex remove everything after 2nd dash

Question

I have a large amount of data that I need to filter using Regex. The data consists of strings that look like this:

60166213

60173866-4533

60167323-9439-1259801

NL170-2683-1262201

60174710-1-A12-4

When I need them to look like this:

60166213

60173866-4533

60167323-9439

NL170-2683

60174710-1

How can I filter with regex to remove everything after and including the 2nd dash. The number of dashes varies, and I need to retain all strings 'as is' that do not contain more than one dash.

Answer 1

You can use a simple regex like this:

(.*?-.*?)-.*

Working demo

You can check on Code generator link the code for different languages. For php that uses PCRE (Perl Comptaible RegEx) engine you can use:

$re = "/(.*?-.*?)-.*/"; 
$str = "60166213\n\n60173866-4533\n\n60167323-9439-1259801\n\nNL170-2683-1262201\n\n60174710-1-A12-4"; 
$subst = "\1"; 

$result = preg_replace($re, $subst, $str);

Answer 2

In Python:

results = [re.sub(r"^([^-]+(?:-[^-]+)?).*$", r"\1", data) for data in datum]

Explained

re.compile("""
    ^                # assert beginning of string
    (                # begin capturing group
        [^-]+        #   one or more non-hyphen characters
        (?:          #   begin non-capturing group
            -        #     literal hyphen
            [^-]+    #     followed by one or more non-hyphen characters
        )?           #   end non-capturing group, and allow 1 or 0 of them
    )                # end capturing group
    .*               # match the rest of the string
    $                # assert end of string""", re.X)

DEMO