wenzelm [Thu, 12 Mar 2009 21:37:18 +0100] rev 30482
simplified versions check_spec, read_spec, check_free_spec, read_free_spec: operate on list of singleton statements;
simplified check_specification, read_specification: operate on a single list of simultaneous statements;
tuned;
wenzelm [Thu, 12 Mar 2009 21:33:06 +0100] rev 30481
removed old named_spec, spec_name, spec_opt_name;
clarified spec vs. specs;
added alt_specs, where_alt_specs -- try to be robust against malformed input;