Estimated hours taken: 5
Branches: main
Fix a bug in the handling of unsatisfiable typeclass constraints.
compiler/typeclasses.m:
If context reduction fails, continue with the type assign set from the
start of context reduction rather than a type assign set supplied by
the caller, which may be missing information that will later be
required.
compiler/typecheck.m:
Don't pass the original type assign set.
tests/invalid/Mmakefile:
tests/invalid/typeclass_test_13.err_exp:
tests/invalid/typeclass_test_13.m:
New test case.
tests/invalid/unsatisfiable_constraint_bug.err_exp:
Update the expected output, now that we have the information
required to produce the correct error meswsage.
Estimated hours taken: 6
Branches: main
In the presence of large amounts of unresolved overloading, the compiler could
consume unbounded amounts of space and time. This diff fixes this problem.
I tried to avoid having this fix lead to a slowdown; in fact, the last three
changes to typecheck_info.m lead to a slight speedup.
compiler/options.m:
doc/user_guide.texi:
Add a new option, --typecheck-ambiguity-error-limit. This gives the
number of type assignments that cause the typechecker to stop
processing further goals. No such facility existed before.
Add a new option, --typecheck-ambiguity-warn-limit. This gives the
number of type assignments that cause the typechecker to emit a
warning. This generalizes the previous hard-coded value in typecheck.m.
Move the definitions of some existing options to the right set of
options.
compiler/typecheck_info.m:
Add the values of the two new options as fields to the typecheck_info,
since we will want to look them up often.
Separate out the error_specs concerned with overloading from the other
error specs, since we want to be able to have an error about excessive
overloading to overwrite a warning about excessive overloading
generated earlier.
Fix a performance bug: the pred_markers were being looked up in the
pred_info each time they were asked for, even though they were also
available directly in a field.
Move the least frequently accessed fields of the typecheck_info
into a separate substructure, to reduce amount of allocation required.
Delete the get and set predicates for the most frequently used fields,
to avoid the overhead of cross-module calls. These fields are now
accessed via field access functions.
compiler/typecheck.m:
Don't typecheck goals if the number of type assignments exceeds
the error limit.
Conform to the changes in typecheck_info.m.
compiler/typecheck_errors.m:
Add a function to generate the new error message.
Conform to the changes in typecheck_info.m.
tests/invalid/ambiguous_overloading_error.{m,err_exp}:
Add this new test case. It is a copy of the existing test case
warnings/ambiguous_overloading, but with more overloading. Old
compilers consume so much memory on it that they eventually run out
and crash, but the new compiler generates an error message
and finishes quickly.
tests/invalid/Mmakefile:
Enable the new test case.
tests/warnings/ambiguous_overloading.exp:
Update the output of this test case to account for the fact that
the context of the warning is now that of the goal *after* the point
at which the number of type assignments exceeds 50, not the goal
*before* this point.
Estimated hours taken: 4
Branches: main
compiler/typeclasses.m:
Fix a bug which could cause non-termination during context
reduction.
tests/valid/Mercury.options:
tests/valid/Mmakefile:
tests/valid/time_yaowl.m:
Test case.
Estimated hours taken: 3
Branches: main
Clean up in unused module imports in the Mercury system detected
by --warn-unused-imports.
analysis/*.m:
browser/*.m:
deep_profiler/*.m:
compiler/*.m:
library/*.m:
mdbcomp/*.m:
profiler/*.m:
slice/*.m:
Remove unused module imports.
Fix some minor departures from our coding standards.
analysis/Mercury.options:
browser/Mercury.options:
deep_profiler/Mercury.options:
compiler/Mercury.options:
library/Mercury.options:
mdbcomp/Mercury.options:
profiler/Mercury.options:
slice/Mercury.options:
Set --no-warn-unused-imports for those modules that are used as
packages or otherwise break --warn-unused-imports, e.g. because they
contain predicates with both foreign and Mercury clauses and some of
the imports only depend on the latter.
Estimated hours taken: 6
Branches: main, release
Fix a bug reported by Peter Ross.
compiler/typeclasses.m:
When recovering after an unsatisfiable constraint, don't merely
delete the existing unproven constraints. Instead construct new
hlds_constraints from scratch. This ensures that the invariants
on it are maintained.
tests/invalid/Mmakefile:
tests/invalid/unsatisfiable_constraint_bug.err_exp:
tests/invalid/unsatisfiable_constraint_bug.m:
Regression test.
Estimated hours taken: 15
Branches: main, release
Implement superclass reduction in the style of CHRs rather than as a top
down search. This is shorter, simpler, and more consistent with the rest
of the typeclass implementation. It also removes a few XXXs and fixes a
bug reported by Julien.
compiler/hlds_data.m:
Add an ancestors field to the hlds_constraint type. This caches
all the ancestors of assumed constraints, along with proofs (in the
form of a sequence of subclass constraints) of how each ancestor is
derived.
Update this field whenever new assumed constraints are created, by
traversing the class hierarchy bottom up.
Delete the old subclass_details type, which was part of the
superclass table.
compiler/typeclasses.m:
Use the cached ancestors to apply the class rules, rather than
performing a top down search.
compiler/type_util.m:
Apply substitutions to the ancestors.
compiler/typecheck.m:
compiler/typecheck_info.m:
Update to account for the additional field.
compiler/*.m:
Remove the superclass table from the module_info and from the
interface to context reduction; it is no longer needed.
compiler/hlds_out.m:
Don't output the superclass table.
tests/valid/Mmakefile:
tests/valid/superclass_bug.m:
Regression test for the bug that is now fixed.
Estimated hours taken: 8
Branches: main
Get rid of a bunch more ambiguities by renaming predicates, mostly
in polymorphism.m, {abstract,build,ordering}_mode_constraints.m, prog_type.m,
and opt_debug.m in the compiler directory and term_io.m, term.m, parser.m,
and string.m in the library.
In some cases, when the library and the compiler defined the same predicate
with the same code, delete the compiler's copy and give it access to the
library's definition by exporting the relevant predicate (in the undocumented
part of the library module's interface).
NEWS:
Mention that the names of some library functions have changed.
library/*.m:
compiler/*.m:
mdbcomp/*.m:
browser/*.m:
Make the changes mentioned above, and conform to them.
test/general/string_test.m:
test/hard_coded/string_strip.m:
test/hard_coded/string_strip.exp:
Conform to the above changes.
Estimated hours taken: 8
Branches: main
Modify the type and purity check passes to gather up all error messages,
and print them all at once after sorting.
compiler/typecheck.m:
compiler/typeclasses.m:
compiler/post_typecheck.m:
compiler/purity.m:
Gather up all error messages instead of printing them when generated.
In some places the gathered list of error specifications allows us
to eliminate error counts and error flags.
Eliminate the last occurrences of io.write_* in these modules,
replacing them with error_specs.
Change the error messages generated by purity.m to eliminate the
unnecessary module qualification of the name of the predicate or
function in which the error occurs.
compiler/typecheck_errors.m:
Turn the predicates here that used to print error messages
into functions that just return the error specification.
compiler/mode_errors.m:
Make a predicate used by post_typecheck.m return an error spec instead
of writing it out.
compiler/typecheck_info.m:
Record the list of errors instead of simple a count of the errors
printed.
compiler/mercury_compile.m:
Print the error message batches returned by type checking and purity
checking.
compiler/error_util.m:
Modify the way we represent severity to allow passes such as
typechecking to count the number of errors *without* printing
anything.
compiler/add_pred.m:
compiler/det_report.m:
compiler/make_hlds_warn.m:
compiler/module_qual.m:
Conform to the change in error_util.m.
compiler/Mercury.options:
Record the fact that some more compiler modules need the workaround
for trace goals.
tests/invalid/*err_exp:
tests/warnings/*exp:
Update the expected output files to conform to the changes above.
This mosly involves expecting sorted messages without duplicates.
Estimated hours taken: 28
Branches: main
A big step towards cleaning up the way we handle errors. The main changes are
- the provision, in error_util.m, of a mechanism for completely specifying
everything to do with a single error in one data structure,
- the conversion of typecheck_errors.m from using io.write_string to
using this new capability,
- the conversion of mode_errors.m and det_report.m from using
write_error_pieces to using this new capability, and
- consistently using the quoting style `symname'/N instead of `symname/N'
in error_util and hlds_error_util (previously, error_util used the former
but hlds_error_util used the latter).
This diff sets up later diffs which will collect all error specifications
in a central place and print them all at once, in order.
compiler/error_util.m:
The new type error_spec, which completely specifies an error.
An error_spec may have multiple components with different contexts
and may have parts which are printed only under certain conditions,
e.g. a given option being set. Each error_spec has a severity
and also records which phase found the error.
The new predicate write_error_spec takes care of updates of the exit
status for errors and (if --halt-at-warn is set) for warnings. It also
takes care of setting the flag that calls for the reminder about -E
at the end.
This diff also makes it simpler to use the ability to print arbitrary
output. It adds the ability to include integers in messages directly,
and the ability to create blank lines. It renames some function symbols
to avoid ambiguities.
Move a predicate that only used by typecheck_errors.m to that file.
compiler/hlds_error_util.m:
Switch to the `symname'/N quoting style for describing predicates and
procedures.
compiler/prog_util.m:
Switch to the `symname'/N quoting style for describing
sym_name_and_arity.
compiler/hlds_module.m:
Provide a predicate to increment the number of errors not by one,
but by the number of errors printed by write_error_spec.
Fix some documentation rot.
compiler/typecheck_errors.m:
Use write_error_spec instead of io.write_strings to print error
messages. In several cases, improve the formatting of the messages
printed.
Mark a number of places where we don't (yet) update the number of
errors in the module_info correctly.
Rename the checkpoint predicate to avoid potential ambiguity with
similar predicates in e.g. mode_info.
compiler/typecheck_info.m:
Group the code for writing stuff out together in one bunch. For each
such predicate, create another that returns a list of format components
instead of doing I/O directly.
compiler/typecheck.m:
Move the code for writing inference messages here from
typecheck_errors.m, since these messages aren't errors.
compiler/mode_errors.m:
compiler/det_report.m:
Use write_error_spec instead of write_error_pieces. In the case of
mode_errors.m, this means we now get correct the set of circumstances
in which we set the flag that calls for the reminder about -E.
compiler/add_pragma.m:
compiler/add_type.m:
Convert some code that used to use write_error_pieces to print error
messages to use write_error_spec instead.
compiler/assertion.m:
compiler/hlds_pred.m:
compiler/post_typecheck.m:
Assertion.m used to contain some code to check for assertions in the
interface that mention predicates that are not exported. Move most
of this code to post_typecheck.m (which is where this code used to be
called from). One small part, which is a test for a particular property
of import_statuses, is moved to hlds_pred.m to be with all the other
similar tests of import_statuses.
compiler/prog_util.m:
Change unqualify_name from a predicate to a function.
compiler/pred_table.m:
compiler/hlds_out.m:
Avoid some ambiguities by adding a suffix to the names of some
predicates.
compiler/*.m:
Conform to the changes above.
library/list.m:
Add a function that was previously present (with different names)
in two compiler modules.
tests/hard_coded/allow_stubs.exp:
Update the format of the expected exception.
tests/invalid/errors2.err_exp2:
Remove this file. As far as I can tell, it was never the correct
expected output on the main branch. (It originated on the alias branch
way back in the mists of time.)
tests/invalid/*.err_exp:
tests/invalid/purity/*.err_exp:
tests/warnings/*.exp:
Update the format of the expected error messages.
tests/recompilation/*.err_exp.2:
Update the format of the expected messages about what was modified.
Estimated hours taken: 8
Branches: main, release
Fix a bug reported by Peter Ross. The problem was that the ancestors of
assumed constraints were not being used to find opportunities for
improvement, which led to some potential improvements being missed.
compiler/hlds_data.m:
Include assumed constraints (and their ancestors) in the set of
redundant constraints, as these can also play a part in improvements
even though they cannot themselves be improved.
compiler/typeclasses.m:
When applying the class improvement rules, don't try to match on
assumed constraints. These are now contained in the redundant
constraints, which we already process.
tests/hard_coded/typeclasses/Mmakefile:
tests/hard_coded/typeclasses/fundeps_5.exp:
tests/hard_coded/typeclasses/fundeps_5.m:
A regression test.
Estimated hours taken: 18
Branches: main
Move the univ, maybe, pair and unit types from std_util into their own
modules. std_util still contains the general purpose higher-order programming
constructs.
library/std_util.m:
Move univ, maybe, pair and unit (plus any other related types
and procedures) into their own modules.
library/maybe.m:
New module. This contains the maybe and maybe_error types and
the associated procedures.
library/pair.m:
New module. This contains the pair type and associated procedures.
library/unit.m:
New module. This contains the types unit/0 and unit/1.
library/univ.m:
New module. This contains the univ type and associated procedures.
library/library.m:
Add the new modules.
library/private_builtin.m:
Update the declaration of the type_ctor_info struct for univ.
runtime/mercury.h:
Update the declaration for the type_ctor_info struct for univ.
runtime/mercury_mcpp.h:
runtime/mercury_hlc_types.h:
Update the definition of MR_Univ.
runtime/mercury_init.h:
Fix a comment: ML_type_name is now exported from type_desc.m.
compiler/mlds_to_il.m:
Update the the name of the module that defines univs (which are
handled specially by the il code generator.)
library/*.m:
compiler/*.m:
browser/*.m:
mdbcomp/*.m:
profiler/*.m:
deep_profiler/*.m:
Conform to the above changes. Import the new modules where they
are needed; don't import std_util where it isn't needed.
Fix formatting in lots of modules. Delete duplicate module
imports.
tests/*:
Update the test suite to confrom to the above changes.
Estimated hours taken: 6
Branches: main
compiler/*.m:
Convert almost all the compiler modules to use . instead of __ as
the module qualifier.
In some cases, change the names of predicates and types to make them
meaningful without the module qualifier. In particular, most of the
types that used to be referred to with an "mlds__" prefix have been
changed to have a "mlds_" prefix instead of changing the prefix to
"mlds.".
There are no algorithmic changes.
Estimated hours taken: 4
Branches: main
Various cleanups for the modules in the compiler directory. The are
no changes to algorithms except the replacement of some if-then-elses
that would naturally be switches with switches and the replacement of
most of the calls to error/1.
compiler/*.m:
Convert calls to error/1 to calls to unexpected/2 or sorry/2 as
appropriate throughout most or the compiler.
Fix inaccurate assertion failure messages, e.g. identifying the
assertion failure as taking place in the wrong module.
Add :- end_module declarations.
Fix formatting problems and bring the positioning of comments
into line with our current coding standards.
Fix some overlong lines.
Convert some more modules to 4-space indentation. Fix some spots
where previous conversions to 4-space indentation have stuffed
the formatting of the code up.
Fix a bunch of typos in comments.
Use state variables in more places; use library predicates
from the sv* modules where appropriate.
Delete unnecessary and duplicate module imports.
Misc. other small cleanups.
Estimated hours taken: 6
Branches: main
Improve the error messages generated for determinism errors involving committed
choice contexts. Previously, we printed a message to the effect that e.g.
a cc pred is called in context that requires all solutions, but we didn't say
*why* the context requires all solutions. We now keep track of all the goals
to the right that could fail, since it is these goals that may reject the first
solution of a committed choice goal.
The motivation for this diff was the fact that I found that locating the
failing goal can be very difficult if the conjunction to the right is
a couple of hundred lines long. This would have been a nontrivial problem,
since (a) unifications involving values of user-defined types are committed
choice goals, and (b) we can expect uses of user-defined types to increase.
compiler/det_analysis.m:
Keep track of goals to the right of the current goal that could fail,
and include them in the error representation if required.
compiler/det_report.m:
Include the list of failing goals to the right in the representations
of determinism errors involving committed committed choice goals.
Convert the last part of this module that wasn't using error_util
to use error_util. Make most parts of this module just construct
error message specifications; print those specifications (using
error_util) in only a few places.
compiler/hlds_out.m:
Add a function for use by the new code in det_report.m.
compiler/error_util.m:
Add a function for use by the new code in det_report.m.
compiler/error_util.m:
compiler/compiler_util.m:
Error_util is still changing reasonably often, and yet it is
included in lots of modules, most of which need only a few simple
non-parse-tree-related predicates from it (e.g. unexpected).
Move those predicates to a new module, compiler_util.m. This also
eliminates some undesirable dependencies from libs to parse_tree.
compiler/libs.m:
Include compiler_util.m.
compiler/notes/compiler_design.html:
Document compiler_util.m, and fix the documentation of some other
modules.
compiler/*.m:
Import compiler_util instead of or in addition to error_util.
To make this easier, consistently use . instead of __ for module
qualifying module names.
tests/invalid/det_errors_cc.{m,err_exp}:
Add this new test case to test the error messages for cc contexts.
tests/invalid/det_errors_deet.{m,err_exp}:
Add this new test case to test the error messages for unifications
inside function symbols.
tests/invalid/Mmakefile:
Add the new test cases.
tests/invalid/det_errors.err_exp:
tests/invalid/magicbox.err_exp:
Change the expected output to conform to the change in det_report.m,
which is now more consistent.
Estimated hours taken: 8
Branches: main
compiler/*.m:
Rename the types 'type', 'inst' and 'mode' to 'mer_type', 'mer_inst'
and 'mer_mode'. This is to avoid the need to parenthesize these type
names in some contexts, and to prepare for the possibility of a parser
that considers those words to be reserved words.
Rename some other uses of those names (e.g. as item types in
recompilation.m).
Delete some redundant synonyms (prog_type, mercury_type) for mer_type.
Change some type names (e.g. mlds__type) and predicate names (e.g.
deforest__goal) to make them unique even without module qualification.
Rename the function symbols (e.g. pure, &) that need to be renamed
to avoid the need to parenthesize them. Make their replacement names
more expressive.
Convert some more modules to four space indentation.
Avoid excessively long lines, such as those resulting from the
automatic substitution of 'mer_type' for 'type'.
Estimated hours taken: 0.5
Branches: main
tools/subst:
A simple tool for performing substitutions on the source files of the
compiler.
compiler/*.m:
Change the names of the get predicates operating on module_infos to
include "get" in the name, for uniformity. This was done mostly by
the following sed script, with some manual cleanup afterwards to reduce
excessive line lengths.
s/module_info_types/module_info_get_type_table/
s/module_info_set_types/module_info_set_type_table/
s/module_info_insts/module_info_get_inst_table/
s/module_info_set_insts/module_info_set_inst_table/
s/module_info_modes/module_info_get_mode_table/
s/module_info_set_modes/module_info_set_mode_table/
s/module_info_ctors/module_info_get_cons_table/
s/module_info_set_ctors/module_info_set_cons_table/
s/module_info_classes/module_info_get_class_table/
s/module_info_set_classes/module_info_set_class_table/
s/module_info_instances/module_info_get_instance_table/
s/module_info_set_instances/module_info_set_instance_table/
s/module_info_superclasses/module_info_get_superclass_table/
s/module_info_set_superclasses/module_info_set_superclass_table/
s/module_info_assertion_table/module_info_get_assertion_table/
s/module_info_exclusive_table/module_info_get_exclusive_table/
s/module_info_ctor_field_table/module_info_get_ctor_field_table/
s/module_info_name/module_info_get_name/
s/module_info_globals/module_info_get_globals/
s/module_info_contains_foreign_types/module_info_get_contains_foreign_types/
s/module_info_num_errors/module_info_get_num_errors/
s/module_info_type_ctor_gen_infos/module_info_get_type_ctor_gen_infos/
s/module_info_stratified_preds/module_info_get_stratified_preds/
s/module_info_unused_arg_info/module_info_get_unused_arg_info/
s/module_info_exception_info/module_info_get_exception_info/
s/module_info_type_spec_info/module_info_get_type_spec_info/
s/module_info_no_tag_types/module_info_get_no_tag_types/
s/module_info_analysis_info/module_info_get_analysis_info/
s/module_info_aditi_top_down_procs/module_info_get_aditi_top_down_procs/
Estimated hours taken: 30
Branches: main
Change the representation of types in the compiler.
We also add some support for handling kinds, which will be used later when we
have a kind system. There are a number of places where kinds are not yet
handled correctly -- we assume that all kinds will be `star'. Each of these
locations is flagged with a comment that contains "XXX kind inference:".
compiler/prog_data.m:
Implement the new version of type (type).
Change the definition of type_param to be a variable instead of a
term, since all parameters must be variables anyway.
Implement versions of varset.merge_* which work with tvarsets and
produce renamings instead of substitutions. Renamings are more
convenient than substitutions because we don't need to know the
kinds of type variables in order to build the renaming, and in any
case the substitutions shouldn't have anything other than variables
in the range so renamings will be more efficient and safe.
Define the type of kinds, and provide a couple of utility predicates
to operate on them.
compiler/prog_io.m:
Parse type definition heads as a sym_name and list of type_params,
rather than a functor. Handle this change in other predicates.
Allow parse errors to be returned by get_with_type/3, and handle
these errors.
Remove parse_type/2. This predicate didn't do any processing, it
just forwarded handling to convert_type/2.
compiler/prog_io_typeclass.m:
Change type_is_functor_and_vars to handle the new representation
of types. In doing so, we retain the old behaviour that pure
predicates pass this test, but no other pred or func types. This
behaviour is arguably incorrect, but there is little point changing
the behaviour at the moment. Instead we should remove these kind of
restrictions entirely, but that should be done later.
compiler/prog_io_util.m:
Provide predicates to both parse and unparse types. We need to
unparse types before printing them out, since we do a lot of special
case handling when printing out terms and we don't want to duplicate
this functionality for types.
compiler/module_qual.m:
Remove report_invalid_type. We now report ill-formed types during
parsing.
compiler/superhomogeneous.m:
Handle errors from the parsing of type expressions.
compiler/prog_out.m:
Provide a predicate to convert builtin_types to their string names,
and vice-versa.
compiler/prog_type.m:
Add a bunch of simple tests to use on types which may have kind
annotations present. In such cases, types do not have a canonical
representation so the simple handling of these tests is not what we
want. (Note that these are only required in early phases. The kind
annotations -- when they are implemented -- will be removed before
type checking.)
Consistently handle the application of renamings, substitutions and
recursive substitutions to various data structures.
compiler/mercury_to_mercury.m:
Implement mercury_output_type, mercury_format_type and
mercury_type_to_string. These convert the type to a term before
formatting -- the reason for this is so that appropriate parentheses
are used when formatting operators. This results in some slight
changes to error messages, which are reflected in changes to the
expected output files in the tests.
Remove the old version of mercury_type_to_string.
Change the argument ordering of mercury_format_var to be consistent
with mercury_format_type. (Other predicates in this module should
probably be changed in a similar way, since this argument ordering
is more amenable to higher-order programming. But that can be left
for another change.)
compiler/type_util.m:
Implement type unification. The behaviour is much the same as the
previous behaviour, except that we now handle apply/N types properly,
and we also allow for kind annotations.
Implement an occurs check for types.
Remove the example definition of replace_eqv_type. It isn't used and
would no longer work anyway even if it would have worked before.
Add a tvar_kind_map field to ctor_defn.
The functions type_info_type and type_ctor_info_type now return
types with `void' as their argument, rather than the type that the
type_info or type_ctor_info was for.
Remove type_util.real_vars/2, since it no longer does anything
different from prog_type.vars/2.
Remove the commented out implementation of type_to_ctor_and_args/3.
Its implementation is in prog_type.m, and has changed significantly
in any case.
compiler/add_clause.m:
Move parse_purity_annotation/3 to prog_io_util.m.
compiler/check_typeclass.m:
Remove apply_substitution_to_var_list/3, since we now have predicates
in prog_type.m to handle such things.
compiler/continuation_info.m:
compiler/trace.m:
Use prog_type.vars/2 instead of type_util.real_vars/2. The two
predicates have the same meaning now since type_infos don't contain
any type variables.
compiler/hlds_data.m:
Add tvar_kind_map fields to hlds_type_defn and hlds_class_defn.
compiler/hlds_pred.m:
Add a tvar_kind_map field to pred_info.
compiler/polymorphism.m:
Add a tvar_kind_map field to poly_info.
Remove unify_corresponding_types, which is no longer used.
compiler/hlds_out.m:
Use mercury_output_type/5 instead of term_io__write_term/4 and
mercury_output_term/5.
compiler/post_typecheck.m:
Build the void substitution directly rather than building intermediate
lists.
compiler/recompilation.version.m:
Use term__list_subsumes instead of type_list_subsumes, which now
operates only on types. This follows up on what was suggested in
an XXX comment.
compiler/typecheck_errors.m:
Use unparse_type/2 to format error messages.
compiler/typecheck_info.m:
Don't export write_type_with_bindings/5. It is no longer used
outside of this module.
compiler/*.m:
Conform to the above changes.
library/rtti_implementation.m:
Fix a syntax error that went undetected in our previous
implementation, and amazingly enough was compiled correctly anyway.
library/term.m:
Move the versions of term__unify, term__unify_list and
term__list_subsumes that were implemented specifically for types
to here. The version of term_unify that takes a list of bound
variables (i.e., variables that should not be bound any further)
is used by the subsumption check, which in turn is used by
recompilation.version.m.
tests/invalid/kind.err_exp:
tests/invalid/tc_err1.err_exp:
tests/invalid/tc_err2.err_exp:
tests/misc_tests/pretty_print_test.exp:
Update the expected output of these tests to match what we now do.
Estimated hours taken: 3
Branches: main
compiler/typeclasses.m:
Use the constraint parameters as "head type parameters" when calling
'eliminate_constraint_by_class_rules'. This fixes a bug whereby
constraints were being reduced even when unsatisfiable, which would
result in polymorphism generating code that was not mode correct.
Also move a call to 'apply_rec_subst_to_constraints' one step up in
the call graph. This puts both calls to this predicate at the same
level, and thereby makes the code easier to understand.
Only call 'apply_rec_subst_to_constraints' on the second occasion
if the bindings have actually changed since the first call. This
is just for the purposes of optimisation.
tests/invalid/Mmakefile:
tests/invalid/unsatisfiable_super.err_exp:
tests/invalid/unsatisfiable_super.m:
New test case to test the bug fix.
Estimated hours taken: 3
Branches: main
Split typecheck.m into smaller modules.
compiler/typecheck.m:
The main typechecking pass.
compiler/typecheck_errors.m:
New module. Error messages and debugging messages.
compiler/typecheck_info.m:
New module. The typecheck_info and type_assign data structures, plus
some basic predicates.
compiler/typeclasses.m:
New module. The context reduction and improvement rules.
compiler/check_hlds.m:
Register the new modules.
compiler/check_typeclass.m:
Call typeclasses instead of typecheck to do context reduction.
compiler/prog_type.m:
Move strip_builtin_qualifiers_from_type(_list) to here.
compiler/hlds_data.m:
Define restrict_list_elements here instead of in typecheck.m and
check_typeclass.m.
