my %input = map { $_->$cgi->param($_) } $cgi->param();
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can be written as:

my %input = map { $_ => scalar $cgi->param($_) } $cgi->param();
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to fix the possible "multiple value" problem, for some version of "fix". (Your arrow was wrong, by the way.)

foreach my $key (keys %input) { 
 $input{$key} =~ tr/*//d; 
 # or whatever makes sense 
}
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can be written as:

tr/*//d for values %input;
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for recent versions of Perl.

-- Randal L. Schwartz, Perl hacker