$~ should be set to the name of the format: 
#!/usr/bin/perl -w
use strict;

my $text1 = "A";
my $text2 = "B";

format COLUMNS =
@<<<<<<@>>>>>>>
$text1,$text2
.

$~ = "COLUMNS"; # note the quotes
write;

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In reply to Re: "use strict" and formats by Joost
in thread "use strict" and formats by mrider

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