By the way, today I've found that in Modern_Perl book, as an example is given @3 as incorrect name: 
These are invalid Perl identifiers:
my $invalid name;  # space is invalid
my @3;             # cannot start with number
my %~flags;        # symbols invalid in name

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(from 4th edition, page #13)

In reply to Re^5: $1[ (reserved != allowed) by rsFalse
in thread $1[ by rsFalse

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