my $profile = {
  required => qw[my_name],
  constraint_methods => {
    my_name => sub {
      my $dfv = shift;
      my $var = shift;

      return if ($var !~ /\d+/);
      return 1;
    }
  }
}

##</code><code>##

$code =<<'END'
    my $dfv = shift;
    my $var = shift;

    return if ($var !~ /\d+/);
    return 1;
END
;
my $profile->{constraint_methods}{my_name} = sub { eval $code }; # Does not work


##</code><code>##

my $profile->{constraint_methods}{my_name} = sub { use Data::Dump qw(dump); warn "PARAMS " . dump(@_) . "\n"; eval $code }; # Does not work