Regex works on chrome and other browsers but returns invalid error on safari

Question

The below regex works on chrome but is having an issue in safari as it contains a lookbehind ,Here in need that lookahead for the proper working so is there any other way by which it could be resolved?

(#[a-zA-Z0-9_(,)]{1,30})+(?<!,)$

The regex im trying to accomplish is :

• That it it should start with #
• Then the string should be seperated by 'comma'
• Then the string could not end with 'comma'
• After 'comma' if a new string is entered then hash should start
• The maxlimit of each string is 30 and min is 1

It should accept:

#tag 
#tag_1,#tag2 
#tag1,#tag2,#tag3 

It should not accept:-

# 
#tag(with more than 30 characters) 
# tag1, 
#tag:///

Answer 1

You can take out the comma of the character class, and prepend it on every iteration

The capture group can be a non capturing one if you need a match only.

^#[a-zA-Z0-9_()]{1,30}(?:,#[a-zA-Z0-9_()]{1,30})*$

The pattern matches:

• ^ Start of string
• #[a-zA-Z0-9_()]{1,30} Match 1-30 repetitions of the character class without the comma
• (?:,#[a-zA-Z0-9_()]{1,30})* Optionally repeat , and 1-30 repetitions of the character class without the comma
• $ End of string

Regex demo