✐‹creator "Kevin Kappelmann"› section ‹Collect› theory Zippy_Collect imports ML_Zipper_Instances Zippy_Nodes begin ML_file‹zippy_collect_trace_mixin_base.ML› ML_file‹zippy_collect_trace_mixin.ML› ML_file‹zippy_node_collect_trace_mixin_base.ML› end