Let's put it in English:

$operator !~ /[^\s+]/

$operator does not match "a character that is not a space nor the plus sign"

I think what you want is:

$operator does not match "a space"

Which would be:

$operator !~ /\s/

Do remember that you're not testing if $operator has only that; you're testing for the existence of one single character in the string (maybe /^\s$/ or /^\s+$/ is what you really want?)

In reply to Re: printing the subscript separator by cog
in thread printing the subscript separator by jacques

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