I guess you can always setup your data outside the closures, just before the benchmark takes place, as in:

use strict;
use warnings;
use Benchmark;

my @strings = qw(exception:tex exception:mex asdf tex:exception:mex);

my @one = @strings;
my @two = @strings;
my @three = @strings;

Benchmark::cmpthese( -5, {
    'one' => sub { my @filtered = grep { /exception:(?!tex)/} @one; },
    'two' => sub { my @filtered = grep { /exception/ && !/tex/ } @two;
+ },
    'three' => sub { my @filtered = grep { /exception:/g && !/\Gtex/ }
+ @three; },
});

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In reply to Re: Initializing iterations while benchmarking by alexm
in thread Initializing iterations while benchmarking by ig

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