Addendum:

podmaster points out that the last example will choke under strict. However on my machine replacing it with Zaxos suggestion

print "Str Eval ret   :",readonly((eval'capture(5)')->[0]);
[download]

Makes strict happy, but the bug remains (at least on my system.)

use strict;
sub capture {\@_};
sub readonly{ my $v=$_[0]; eval{$_[0]=$v;1} ? 0 : 1 }

$\="\n";
print "No eval        :",readonly(capture(5)->[0]);
eval '
print "In str eval    :",readonly(capture(5)->[0]);
';
eval {
print "In block eval  :",readonly(capture(5)->[0]);
};
print "Block Eval ret :",readonly(eval{capture(5)}->[0]);
print "Str Eval ret   :",readonly((eval'capture(5)')->[0]);
__END__
No eval        :1
In str eval    :1
In block eval  :1
Block Eval ret :1
Str Eval ret   :0
[download]

Yves / DeMerphq
---
Writing a good benchmark isnt as easy as it might look.