I believe you're looking for the __DATA__ filehandle. Stick it at the end of your code, and you can treat it just as if you'd opened a regular file.

while (<DATA>) {
  # do stuff with $_
}
# ...or a slurp
seek(DATA,0);
my $data = (<DATA>);

# end of script
__DATA__
    # Data
    # Data
    # Data
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Cheers, Ben.