2017-04-10 ago explicit theory qualifier for session "HOL-Proofs": its theory name space overlaps with session "HOL", even for further imports;
2017-04-09 ago added system option record_proofs, which allows to build HOL-Proofs without special Proofs.thy;
2017-03-15 ago dynamic session_options for tuning parameters and initial prover options;
2017-03-07 ago clarified modules;
2017-02-27 ago clarified defaults;
2016-11-24 ago explicit option editor_generated_input_delay, which is more aggressive by default;
2016-10-20 ago prevent sporadic disconnection;
2016-10-19 ago added system option "profiling";
2016-10-10 ago clarified treatment of options;
2016-10-01 ago options for process policy, notably for multiprocessor machines;
2016-09-08 ago option "checkpoint" helps to fine-tune global heap space management;
2016-04-06 ago simplified bootstrap: critical structures remain accessible in ML_Root context;
2016-04-05 ago clarified bootstrap environment;
2016-04-04 ago option ML_system_unsafe;
2016-04-01 ago lower threshold -- command timing for proofs is cumulative, e.g. HOL 672 ~> 8889;
2016-04-01 ago less bulky timing information, e.g. HOL 56913 ~> 672;
2016-04-01 ago tuned whitespace;
2016-03-26 ago avoid hardwired values;
2016-03-02 ago support for ML_exception_debugger;
2016-02-25 ago proper option process_output_tail, more generous default;
2016-01-10 ago prune old versions more often, to reduce overall heap requirements;
2015-12-19 ago prune old document versions more frequently, for reduced heap usage;
2015-11-09 ago prefer explicit State panel;
2015-11-08 ago added option timeout_scale;
2015-11-07 ago clarified completion of explicit symbols (see also f6bd97a587b7, e0e4ac981cf1);
2015-11-02 ago clarified completion of Isabelle symbols within document source;
2015-09-21 ago option editor_output_state;
2015-09-11 ago convenient change of ML system architecture via system option ML_preference_64, which is grepped off-line from stored preferences during bootstrap;
2015-08-11 ago init/exit depending on active debugger panels;
2015-08-10 ago eliminated global option: breakpoints control this individually;
2015-08-05 ago more controls;
2015-08-05 ago tuned signature;
2015-07-21 ago support for ML debugger;
2015-07-16 ago added option ML_debugger;
2015-04-15 ago GUI controls for ML_statistics, for more digestible protocol dump;
2015-01-29 ago explicit threads_stack_limit (for recent Poly/ML SVN versions), which leads to soft interrupt instead of exhaustion of virtual memory, which is particularly relevant for the bigger address space of x86_64;
2015-01-25 ago discontinued obsolete option "document_graph";
2014-12-22 ago system option "pretty_margin" is superseded by "thy_output_margin";
2014-10-31 ago discontinued pointless option: timing is always on (overall theory only);
2014-08-13 ago added option editor_syslog_limit;
2014-08-05 ago added system option editor_output_delay: lower value might help big sessions under low-memory situations;
2014-05-06 ago explicit option parallel_print to downgrade parallel scheduling, which might occasionally help for big and heavy "scripts";
2014-04-25 ago suppress potential dangerous option (see 1baa5d19ac44);
2014-04-17 ago tuned option name;
2014-03-25 ago clarified options ML_source_trace and ML_exception_trace (NB: the latter needs to be a system option, since the context is sometimes not available, e.g. for 'theory' command);
2014-03-24 ago discontinued Toplevel.debug in favour of system option "exception_trace";
2014-02-22 ago support for completion within the formal context;
2013-08-25 ago discontinued parallel_subproofs_saturation and related internal counters (superseded by parallel_subproofs_threshold and timing information);
2013-07-31 ago simplified / clarified execution priority: auto prints << 0, proofs < 0, eval = 0, print_state = 1;
2013-07-31 ago simplified flag for continuous checking: avoid GUI complexity and slow checking of all theories (including prints);
2013-07-30 ago recovered delay for Document.start_execution (see also 627fb639a2d9), which potentially improves throughput when many consecutive edits arrive;
2013-07-29 ago NEWS;
2013-07-29 ago afford higher execution priority by default: defer proofs and thus stretch parallelism over whole document;
2013-07-29 ago support declarative editor_execution_range, instead of old-style check/cancel buttons;
2013-07-27 ago discontinued historic document formats;
2013-07-20 ago option editor_execution_priority;
2013-07-20 ago obscure options;
2013-07-19 ago just one option "skip_proofs", without direct access within the editor (it makes document processing stateful without strong reasons -- monotonic updates already handle goal forks smoothly);
2013-07-18 ago proper system options for 'find_theorems';
2013-06-30 ago tuned;