From @LLFourn

perl6 -e 'use Test do { Date.new(year => 2015); ()}'

===SORRY!===
Default constructor for 'Date' only takes named arguments

This example is fairly golfed, but you can run into this in the wild.

Consider a module that has an EXPORT sub and takes positional arguments. If
you tried to do

use MyModule Date.new( year => 2015) # you will get the error

2¢

I don't really get why the arguments to 'use' don't just use normal
invocation semantics, with the positionals taken out and passed to export
and the named used for normal importing.

unless $*IN_DECL eq 'use' || $*IN_DECL eq 'no' || $*IN_DECL eq 'import' ||
$*IN_RETURN {

  $_[2].named($name);

  }
This is the line in Actions.nqp that makes 'use' special.