Estimated hours taken: 8
Implement declarative debugging of code that throws exceptions.
This aborts if used on code that handles exceptions. There is no point
dealing with this yet, since the oracle won't handle the higher order
argument to try/2.
browser/declarative_debugger.m:
Add "unexpected exception" questions and "unhandled exception" bugs,
and generate these from EXCP events. Handle the exception case
in various switches.
Add a predicate unexpected_exception_children/4, analogous to
{wrong,missing}_answer_children/4.
browser/declarative_execution.m:
Add excp/5 nodes to the event trace, and export a C function to
construct them. Handle these nodes in various switches.
Allow contours to extend beyond NEGE events, if the status is
`undecided'. Such events have no matching NEGS or NEGF event,
so they do not mark the boundary of a separate context.
browser/declarative_oracle.m:
Store information about which exceptions should/shouldn't be thrown
from various calls, and use this information to answer questions
where possible.
browser/declarative_user.m:
Handle the new questions and bugs.
trace/mercury_trace_declarative.c:
Add a function to deal with EXCP events.
trace/mercury_trace_internal.c:
Allow declarative debugging to be started from EXCP events.
tests/debugger/declarative/Mmakefile:
tests/debugger/declarative/throw.m:
tests/debugger/declarative/throw.inp:
tests/debugger/declarative/throw.exp:
tests/debugger/declarative/throw.exp2:
A test case for this feature.
tests/debugger/declarative/queens.exp:
Update the output from this test.
Estimated hours taken: 10
Represent bugs directly rather than with edt nodes. This makes the
interface to the analyser more consistent: bugs are now handled
in much the same way as questions.
browser/declarative_analyser.m:
- In the mercury_edt/2 typeclass, change edt_root/3 to
edt_root_question/3 and add the method edt_root_e_bug/3.
- Add the type prime_suspect/1 which keeps track of the
evidence (oracle answers) which implicates a particular
edt node.
- Use the new bug representation.
browser/declarative_debugger.m:
browser/declarative_oracle.m:
- Move oracle_confirmation to declarative_debugger.m, and
rename it decl_confirmation.
browser/declarative_debugger.m:
- Change decl_bug/1 to decl_bug/0. Instead of a bug being
represented by an edt node, decl_bug now represents
directly the different sorts of bugs possible.
- Add an implementation for the new mercury_edt method.
browser/declarative_oracle.m:
browser/declarative_user.m:
- Update the confirmation to use the new types.
tests/debugger/declarative/*.{exp,exp2}:
- Update test results.
Estimated hours taken: 15
Fix the user interface of the declarative debugger so that it
produces more readable output; the representation of atoms
is updated so that it can handle non-ground arguments.
Ensure that all DD output goes through the correct stream, so that
the debugger works properly under emacs.
browser/declarative_debugger.m:
Call a procedure in the oracle to handle bug confirmation
(including printing out the bug), rather than handle
it directly.
browser/declarative_execution.m:
Update the trace_atom type so that it can handle both ground
and free arguments. Export to C some procedures for
constructing trace atoms.
browser/declarative_oracle.m:
Export a procedure which handles bug confirmation. This calls
the declarative_user module to do the interaction, and interprets
the result.
browser/declarative_user.m:
Export a procedure to handle bug confirmation by the user.
Update to handle the changes to trace_atom.
trace/mercury_trace_declarative.c:
Construct trace_atoms by calling the new Mercury procedures
exported from browser/declarative_execution.m.
trace/mercury_trace_declarative.h:
Remove the macro that had been used to construct old style atoms.
trace/mercury_trace_vars.{c,h}:
Export a procedure to calculate the argument position of a
head variable.
tests/debugger/declarative/Mmakefile:
tests/debugger/declarative/args.{m,inp,exp,exp2}:
New test case to test mixing bound and free arguments.
tests/debugger/declarative/*.inp:
tests/debugger/declarative/*.exp:
tests/debugger/declarative/*.exp2:
Update test cases to reflect new output, and the extra question
asked for bug confirmation.
Estimated hours taken: 1
Make all the modules in the browser library sub-modules of
module `mdb', to avoid link errors when users use module names
such as `parse'.
browser/Mmakefile:
browser/browser_library.m:
browser/mdb.m:
Rename browser_library.m to mdb.m.
Change `:- import_module' declarations to
`:- include_module' declarations.
browser/Mmakefile:
Remove the special case rule for `mer_browser.init' --
it doesn't work when the file names are not the same
as the module name. Instead, the default rule for `mdb.init'
is used and the output is copied to `mer_browser.init'.
browser/.cvsignore:
Rename header files, etc.
browser/*.m:
Add a `mdb__' prefix to the names of modules in the browser library
in `:- module' and `:- import_module' declarations.
trace/*.c:
Rename the header files for the browser library in
`#include' statements.
tests/hard_coded/Mmakefile:
tests/hard_coded/parse.m:
tests/hard_coded/parse.exp:
Test case.
Estimated hours taken: 120
Implement the new architecture for the front end of the
declarative debugger. Disable declarative debugging if conservative
GC is not being used since this change relies on it. The benefits
of declarative debugging in non-GC grades are not worth the extra
maintenance required to support it, since even small examples require
a large amount of memory.
browser/declarative_analyser.m:
New module which handles the analysis of EDTs, which was
previously done in browser/declarative_debugger.m.
browser/declarative_debugger.m:
- Change the interface according to the new design.
- Export types of the form decl_*, rather than edt_*.
- Move the EDT analysis to the new module.
- Handle the interaction between the analyser and the oracle.
- Don't interact directly with the user, but go via the oracle.
- New diagnoser state type.
- Update the EDT instance to conform to the other changes.
browser/declarative_oracle.m:
- Replace oracle_answer type with oracle_response.
- Allow the oracle to work with a queue of questions rather
than one at a time.
- Add new predicates to manipulate the knowledge base.
browser/declarative_user.m:
- Export the user_state type.
- Handle some user commands in this module.
- Handle questions properly (apart from printing atoms).
browser/browser_library.m:
Add the new module.
trace/mercury_trace_declarative.c:
- Initialise the front end state just once per session.
- Make the step size much larger, since implicit subtrees
are not fully supported yet.
- Correct the types in a format specifier.
trace/mercury_trace_declarative.c:
trace/mercury_trace_internal.c:
trace/mercury_trace_internal.h:
- Disable declarative debugging unless conservative GC is used.
Estimated hours taken: 55
This change adds a more sophisticated oracle to the declarative
debugger. The oracle now tries to remember previous answers and uses
them if available, and only asks the user if there is no other
information.
browser/declarative_oracle.m:
- Add the type "oracle_assumption", which identifies an
internal assumption of the oracle.
- Add the type "oracle_answer", which the oracle returns to the
caller. This holds either the truth value, or a reason why
the truth value cannot be given yet.
- Implement a knowledge base to store the previous answers.
This data structure is designed to be able to store arbitrary
assertions, although at this stage only one kind of assertion
is used.
- Where possible, use the KB to answer questions, instead of
asking the user.
- Update comments.
browser/declarative_debugger.m:
- Use the new interface to the oracle. Handle "don't know"
answers in a simple way: either save the question and ask it
later or return without finding any bug.
- Move the debugger_command type to this module.
- Move the UI stuff to a new module.
browser/declarative_user.m:
New module to handle interaction between the debugger/oracle
and the user.
tests/debugger/declarative/Mmakefile:
tests/debugger/declarative/oracle_db.{m,inp,exp}
Add a test case for the new feature.
Estimated hours taken: 6
If calling from the internal debugger, use readline input for the
interactive term browser and interactive queries.
browser/browse.m:
Change some if-then-elses to switches, which will help
catch errors if a new functor is added to the debugger type.
browser/parse.m:
browser/util.m:
Return a string from util__trace_getline/4 rather than a
list of chars, which saves converting from a string to a list
of chars and then back again.
browser/util.m:
Add a version of util__trace_getline that also takes I/O
stream arguments. Pass these arguments to MR_trace_getline.
browser/declarative_oracle.m:
Call util__trace_getline/4 to do input via readline (if
available). Improve error handling.
browser/interactive_query.m:
Call util__trace_getline to get user input, instead of
standard library predicates.
runtime/mercury_init.h:
runtime/mercury_wrapper.c:
runtime/mercury_wrapper.h:
trace/mercury_trace_internal.c:
trace/mercury_trace_internal.h:
Add two I/O stream arguments to MR_trace_getline.
Estimated hours taken: 12
Clean up the declarative debugger.
browser/declarative_debugger.m:
browser/declarative_oracle.m:
- Add a new type, oracle_data, to store the oracle database.
- Thread an oracle database through a single call to the
front end.
- Replace `unknown' with a less overloaded name in
some type definitions.
trace/mercury_trace_declarative.c:
trace/mercury_trace_declarative.h:
browser/declarative_debugger.m:
- Improve documentation.
browser/declarative_debugger.m:
- Export new type, edt_truth.
- Improve the interface to the oracle.
- Add a new typeclass, evaluation_tree, and update the
previous interface to reflect this.
- Make declarative_bug a polymorphic type, and change the
constructor for buggy nodes from `wrong' to `e_bug'.
Estimated hours taken: 80
Add a front end to the declarative debugger, written in Mercury. Modify
the back end to call this whenever an EDT is built. Also, various
bug fixes and improvements.
browser/declarative_debugger.m:
New module. This is a first implementation of the front end of
the declarative debugger. It uses a simple top-down algorithm
to search the EDT for a buggy node. The results are printed
in a simple format to the output stream. It is called from the
back end, in trace/mercury_trace_declarative.c.
browser/declarative_oracle.m:
New module. This is a first implementation of an oracle for the
declarative debugger. It simply passes all queries directly
on to the user.
browser/browser_library.m:
Import the new modules.
trace/mercury_trace_declarative.c:
- Various fixes/improvements of comments.
- Fix bugs where `int' is used instead of `Unsigned'.
- Pass the event_info structure to MR_trace_decl_update_path,
rather than passing various components of it.
- Use the copy of MR_trace_event_number in the event_info structure
rather than referring to the global variable directly.
- Remove the EDT printing functions, as they have been superseded by
the new front end. Call the new front end instead of these old
functions.
- Provide an interface to the EDT nodes that is imported by the
front end.
- Ensure that, after diagnosis, we end up at the same event we
started at.
- Fix a bug where it was assumed all procedures had at least one
argument.
- Ensure that the user is notified if the dd_wrong operation cannot
be started due to MR_trace_retry failing.
trace/mercury_trace_declarative.h:
- Move a #include to the correct place.
- Declare the interface to the EDT nodes.
trace/mercury_trace_internal.c:
Fix a bug introduced earlier.
runtime/mercury_conf_param.h:
Add a new configuration macro, MR_DEBUG_DD_BACK_END. When defined
this causes information about the declarative debugger back end
to be printed out during operation.
