Correct test for new flattening semantics.
Correct test for new flattening semantics.

Add a flat, and fix [[1]] which runs into the single value rule.

perl6/roast,skids/roast,bitrauser/roast,skids/roast,zostay/roast,cygx/roast,dankogai/roast,skids/roast,b2gills/roast,zostay/roast,dogbert17/roast,zostay/roast,dankogai/roast,dogbert17/roast,dankogai/roast,b2gills/roast,b2gills/roast,cygx/roast,bitrauser/roast,cygx/roast