use Test::LectroTest;

    Property {
        ##[ h <- Hash( Int, Int ) ]##
        are_hashes_equal( $h, $h ) == 1;
    }, name => "equal hashes are recognized as equal";

    Property {
        ##[ h <- Hash( Int, Int, length=>[1,] ) ]##
        my %h_diff = %$h;
        delete $h_diff{scalar each %$h};  # delete 1st key
        are_hashes_equal( $h, \%h_diff ) == 0;
    }, name => "differences in quantity of keys are detected";

    Property {
        ##[ h <- Hash( Int, Int, length=>[1,] ) ]##
        my %h_diff = %$h;
        delete $h_diff{scalar each %$h};  # delete 1st key
        $h_diff{a} = 1;                   # replace with "a" key
        are_hashes_equal( $h, \%h_diff ) == 0;
    }, name => "differences in values of keys are detected";

    Property {
        ##[ h <- Hash( Int, Int, length=>[1,] ) ]##
        my %h_diff = %$h;
        $h_diff{scalar each %$h}++;  # increment 1st value
        are_hashes_equal( $h, \%h_diff ) == 0;
    }, name => "differences in values are detected";