9 months ago wenzelm 2019-08-13 added SUBPROOFS / "subproofs" method combinator, for more compact proofterms;
2018-05-09 wenzelm 2018-05-09 clarified future scheduling parameters, with support for parallel_limit;
2018-02-19 wenzelm 2018-02-19 misc tuning and clarification;
2015-06-06 wenzelm 2015-06-06 more tight treatment of subgoals: main goal may refer to extra variables;
2014-11-08 wenzelm 2014-11-08 optional proof context for unify operations, for the sake of proper local options;
2014-08-19 wenzelm 2014-08-19 clarified modules;