Regular Expressions 101

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~
^(?=(?:[^\n\d]*\d){4})[-0-9_,/\s]+$
~
gm
^ asserts position at start of a line
Positive Lookahead
(?=(?:[^\n\d]*\d){4})
Assert that the Regex below matches
Non-capturing group
(?:[^\n\d]*\d){4}
{4} matches the previous token exactly 4 times
Match a single character not present in the list below
[^\n\d]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\n matches a line-feed (newline) character (ASCII 10)
\d matches a digit (equivalent to [0-9])
\d matches a digit (equivalent to [0-9])
Match a single character present in the list below
[-0-9_,/\s]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
- matches the character - literally (case sensitive)
This hyphen is treated literally, which might be confusing for others. Consider escaping it or placing at the start or end of the class!
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
_,/ matches a single character in the list _,/ (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
$ asserts position at the end of a line
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

~
~
gm

Test String