I'm having trouble figuring out what exactly this regex pattern is searching for mostly due to the number at the end. From what I can tell, it is saying search for any character that is not a-z and repeat it for the whole string. What does the 3 do?
In a character class all characters loose their special meaning (if any), only the first
^ is used to negate the class,
- is used to define a range (except at the first and last position), an eventual backslash may start an escape sequence and
] closes the class.
3 is the literal character
+ is the literal character
. is a literal
., nothing more.
[^a-z.+3] matches one character that isn't in this list and is the same as