Firstly, I'm not planning on breaking compatibility with Type::Params. The new API would live under a different namespace, such as Type::Params2.

The API for Type::Params is currently:

use feature 'state';
use Type::Params qw( compile compile_named_oo );
use Types::Standard -types;

sub function_with_positional_parameters {
  state $check = compile( ArrayRef, Int, Int );
  my ( $list, $start, $end ) = $check->( @_ );

  my @slice = @{$list}[ $start .. $end ];
  return \@slice;
}

sub function_with_na…