use IO::String;
use strict;

my $io = tie(*TEST,'IO::String');

my $temp = $io->string_ref;

my $t1 = '1';
my $t2 = '2';
my $t3 = '3';

select(TEST);

write();

format TEST=
@||| @||| @|||
$t1,$t2,$t3
.

select(STDOUT);
print $$temp;