A "safe string" is composed of one or more alphanumeric characters, with underscore also available, but the first character has to be a letter or a dash. You could define this as a regular expression: /\-?A-Za-z_A-Za-z0-9_*/.
What about letters outside the ASCII range? Perl allows Unicode letters as variable names, for example. Do barewords here get the same treatment? $α{niņa}=5;

In reply to Re: Re: using quotes in hash keys by John M. Dlugosz
in thread using quotes in hash keys by thefid

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