Form the free online Perl documentation (perldata):
In fact, an identifier within such curlies is forced to be a string, as is any simple identifier within a hash subscript. Neither need quoting. Our earlier example, $days{'Feb'} can be written as $days{Feb} and the quotes will be assumed automatically. But anything more complicated in the subscript will be interpreted as an expression.

Perl is case-sensitive. So are hash keys.

In reply to Re: beginner question - why is hash key unquoted and in capitals by toolic
in thread beginner question - why is hash key unquoted and in capitals by Anonymous Monk

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