A nit-pick, but the substitution should really be 

s/.//s

[download]
to be equivalent with the others. Note the s modifier; it makes . match leading newlines as well. Otherwise you remove the first non-newline character from the string. 
my %ex = (
    "\n" . 'regexp'   => sub { s/.// },
    "\n" . 'regexp/s' => sub { s/.//s },
    "\n" . 'chop'     => sub { $_ = reverse; chop; $_ = reverse; },
    "\n" . 'substr1'  => sub { substr($_,0,1) = '' },
    "\n" . 'substr2'  => sub { $_ = substr($_,1) },
);

for (sort keys %ex) {
    $ex{$_}->();
    print "[$_]\n";
}

__END__
[chop]
[
egexp]
[regexp/s]
[substr1]
[substr2]

[download]

Update: Added example.

lodin

In reply to Re: Ways to delete start of string (The /s modifier) by lodin
in thread Ways to delete start of string by hsmyers

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