Although it's tempting to use eval in a situation like this, I prefer (ab)using coderefs, either by employing a hash of anonymous subs (rather than subs proper)...

package atm;

my %code = (
  var1 => sub { print 1 },
  var2 => sub { print 2 },
    # ...
  varN => sub { print N },
);

package main;

if ( exists $atm::code{$varN} ) {
  $atm::code{$varN}->( object_vars($var1) );
} else {
  # no matching sub
}
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... or testing for the existance of the sub you want to run with can, and executing the coderef it returns.

if ( my $sub = atm->can($varN) ) {
  $sub->( object_vars($varN) );
} else {
  # no matching sub
}
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    --k.