recent changes in ext-rep

[Peter Dobcsanyi]

Recent fixes, changes, additions in the ext-rep schema.

<alternative_representations>

    This new optional subtree has been inserted into <block_design> to
    accommodate, well, alternative representations. For version 1.0,
    the only alt-rep is <incidence_matrix>.

<function_on_ ...>

    The two-level <map>, <map_entry> encapsulation of the body of a
    function has been eliminated. Now, the body of a function is a
    series of <map>-s.

    Yet one more "contraction" has been added, allowing a function to
    have a <blank> entry with the requirements that the otherwise
    optional 'image_cardinality' property must be present in this
    variant.

<statistical_properties>

    In <canonical_variances> and in <efficiency_factors> the 'length'
    has been replaced with 'no_distinct'.

    Since subtrees of <optimality_criteria> and <efficiency_factors> are
    not optional (with only one exception) their order has been made
    fixed.

    Some minor fixes.

For further details, please consult "design.rnc" revision 1.74.

--             ,
    Peter Dobcsanyi