the substring can conatin commas in it

Sorry, this doesn't make sense to me. If the input string is "1,2,3,4,5,6,7", then does $a get "1,2", or does $b get "2,3", and so on...

Or is this CSV, as swl correctly pointed out? Then you should use Text::CSV.

If not, then as I said, please provide lots of examples of valid input with the expected output, as well as lots of examples of invalid input.

In reply to Re^3: check if string is valid with special cases by haukex
in thread check if string is valid with special cases by ovedpo15

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