Files
mercury/compiler/add_class.m
Zoltan Somogyi a79bdd9a6b Split clause_to_proc.m into three pieces.
compiler/default_func_mode.m:
compiler/introduce_exists_casts.m:
    Carve these two modules out of clause_to_proc.m. The code now in
    default_func_mode.m had no connection to the rest of clause_to_proc.m,
    while the code now in introduce_exists_casts.m has only a single call
    to a predicate defined in the left-over part of clause_to_proc.m.

compiler/clause_to_proc.m:
    Remove the code that has been moved elsewhere, and export that one
    predicate for introduce_exists_casts.m. This reduces clause_to_proc.m
    to less than half its former size.

compiler/check_hlds.m:
    Add introduce_exists_casts.m to the check_hlds package.

compiler/hlds.m:
    Add default_func_mode.m to the hlds package.

compiler/notes/compiler_design.html:
    Document the new modules.

compiler/add_class.m:
compiler/add_clause.m:
compiler/du_type_layout.m:
compiler/make_hlds_passes.m:
compiler/modes.m:
compiler/polymorphism.m:
    Conform to the changes above.
2017-12-18 18:40:20 +11:00

811 lines
34 KiB
Mathematica

%-----------------------------------------------------------------------------%
% vim: ft=mercury ts=4 sw=4 et
%-----------------------------------------------------------------------------%
% Copyright (C) 1993-2012 The University of Melbourne.
% This file may only be copied under the terms of the GNU General
% Public License - see the file COPYING in the Mercury distribution.
%-----------------------------------------------------------------------------%
:- module hlds.make_hlds.add_class.
:- interface.
:- import_module hlds.hlds_module.
:- import_module hlds.hlds_pred.
:- import_module hlds.make_hlds.qual_info.
:- import_module parse_tree.
:- import_module parse_tree.error_util.
:- import_module parse_tree.prog_data.
:- import_module list.
:- import_module term.
%-----------------------------------------------------------------------------%
:- pred add_typeclass_defn(sec_item(item_typeclass_info)::in,
module_info::in, module_info::out,
list(error_spec)::in, list(error_spec)::out) is det.
:- pred add_instance_defn(ims_item(item_instance_info)::in,
module_info::in, module_info::out,
list(error_spec)::in, list(error_spec)::out) is det.
% Given the definition for a predicate or function from a type class
% instance declaration, produce the clauses_info for that definition.
%
:- pred do_produce_instance_method_clauses(instance_proc_def::in,
pred_or_func::in, arity::in, list(mer_type)::in,
pred_markers::in, term.context::in, instance_status::in, clauses_info::out,
tvarset::in, tvarset::out, module_info::in, module_info::out,
qual_info::in, qual_info::out, list(error_spec)::in, list(error_spec)::out)
is det.
%-----------------------------------------------------------------------------%
%-----------------------------------------------------------------------------%
:- implementation.
:- import_module hlds.default_func_mode.
:- import_module hlds.hlds_args.
:- import_module hlds.hlds_data.
:- import_module hlds.hlds_goal.
:- import_module hlds.hlds_rtti.
:- import_module hlds.make_hlds.add_clause.
:- import_module hlds.make_hlds.add_pred.
:- import_module hlds.make_hlds.make_hlds_error.
:- import_module hlds.make_hlds.make_hlds_warn.
:- import_module hlds.make_hlds.state_var.
:- import_module hlds.pred_table.
:- import_module hlds.vartypes.
:- import_module mdbcomp.
:- import_module mdbcomp.sym_name.
:- import_module parse_tree.maybe_error.
:- import_module parse_tree.prog_type.
:- import_module parse_tree.prog_type_subst.
:- import_module parse_tree.prog_util.
:- import_module parse_tree.set_of_var.
:- import_module bool.
:- import_module int.
:- import_module map.
:- import_module require.
:- import_module set.
:- import_module varset.
add_typeclass_defn(SectionItem, !ModuleInfo, !Specs) :-
SectionItem = sec_item(SectionInfo, ItemTypeClassInfo),
SectionInfo = sec_info(ItemMercuryStatus, NeedQual),
item_mercury_status_to_typeclass_status(ItemMercuryStatus,
TypeClassStatus0),
ItemTypeClassInfo = item_typeclass_info(ClassName, ClassParamVars,
Constraints, FunDeps, Interface, VarSet, Context, _SeqNum),
module_info_get_class_table(!.ModuleInfo, Classes0),
list.length(ClassParamVars, ClassArity),
ClassId = class_id(ClassName, ClassArity),
(
Interface = class_interface_abstract,
typeclass_make_status_abstract(TypeClassStatus0, TypeClassStatus1)
;
Interface = class_interface_concrete(_),
TypeClassStatus1 = TypeClassStatus0
),
HLDSFunDeps = list.map(make_hlds_fundep(ClassParamVars), FunDeps),
( if map.search(Classes0, ClassId, OldDefn) then
OldDefn = hlds_class_defn(OldTypeClassStatus, OldConstraints,
OldFunDeps, _OldAncestors, OldClassParamVars, _OldKinds,
OldInterface, OldMethods, OldVarSet, OldContext),
% The typeclass is exported if *any* occurrence is exported,
% even a previous abstract occurrence.
typeclass_combine_status(TypeClassStatus1, OldTypeClassStatus,
TypeClassStatus),
(
OldInterface = class_interface_concrete(_),
ClassMethods0 = OldMethods,
ClassInterface = OldInterface
;
OldInterface = class_interface_abstract,
ClassMethods0 = [],
ClassInterface = Interface
),
( if
% Check that the superclass constraints are identical.
not constraints_are_identical(OldClassParamVars, OldVarSet,
OldConstraints, ClassParamVars, VarSet, Constraints)
then
% Always report the error, even in `.opt' files.
Extras = [words("The superclass constraints do not match."), nl],
report_multiple_def_error(ClassName, ClassArity, "typeclass",
Context, OldContext, Extras, !Specs),
ErrorOrPrevDef = bool.yes
else if
not class_fundeps_are_identical(OldFunDeps, HLDSFunDeps)
then
% Always report the error, even in `.opt' files.
Extras = [words("The functional dependencies do not match."), nl],
report_multiple_def_error(ClassName, ClassArity, "typeclass",
Context, OldContext, Extras, !Specs),
ErrorOrPrevDef = bool.yes
else if
Interface = class_interface_concrete(_),
OldInterface = class_interface_concrete(_)
then
( if TypeClassStatus = typeclass_status(status_opt_imported) then
true
else
Extras = [],
report_multiple_def_error(ClassName, ClassArity, "typeclass",
Context, OldContext, Extras, !Specs)
),
ErrorOrPrevDef = bool.yes
else
ErrorOrPrevDef = bool.no
),
IsNewDefn = bool.no
else
IsNewDefn = bool.yes,
ErrorOrPrevDef = bool.no,
ClassMethods0 = [],
ClassInterface = Interface,
TypeClassStatus = TypeClassStatus1
),
(
ErrorOrPrevDef = yes
;
ErrorOrPrevDef = no,
(
Interface = class_interface_concrete(Methods),
module_add_class_interface(ClassName, ClassParamVars,
TypeClassStatus, yes(ItemMercuryStatus), NeedQual,
Methods, PredProcIds0, !ModuleInfo, !Specs),
% Get rid of the `no's from the list of maybes.
list.filter_map(maybe_is_yes, PredProcIds0, PredProcIds1),
% The list must be sorted on pred_id and then proc_id --
% check_typeclass.m assumes this when it is generating the
% corresponding list of pred_proc_ids for instance definitions.
list.sort(PredProcIds1, ClassMethods)
;
Interface = class_interface_abstract,
ClassMethods = ClassMethods0
),
% Ancestors is not set until check_typeclass.
Ancestors = [],
% XXX kind inference:
% We set all the kinds to `star' at the moment. This should be
% done differently when we have a proper kind system.
Kinds = map.init,
ClassDefn = hlds_class_defn(TypeClassStatus, Constraints, HLDSFunDeps,
Ancestors, ClassParamVars, Kinds, ClassInterface, ClassMethods,
VarSet, Context),
map.set(ClassId, ClassDefn, Classes0, Classes),
module_info_set_class_table(Classes, !ModuleInfo),
(
IsNewDefn = yes,
% When we find the class declaration, make an entry
% for the instances.
module_info_get_instance_table(!.ModuleInfo, Instances0),
map.det_insert(ClassId, [], Instances0, Instances),
module_info_set_instance_table(Instances, !ModuleInfo)
;
IsNewDefn = no
)
).
:- func make_hlds_fundep(list(tvar), prog_fundep) = hlds_class_fundep.
make_hlds_fundep(TVars, fundep(Domain0, Range0)) = fundep(Domain, Range) :-
Domain = make_hlds_fundep_2(TVars, Domain0),
Range = make_hlds_fundep_2(TVars, Range0).
:- func make_hlds_fundep_2(list(tvar), list(tvar)) = set(hlds_class_argpos).
make_hlds_fundep_2(TVars, List) = list.foldl(Func, List, set.init) :-
Func = (func(TVar, Set0) = set.insert(Set0, N) :-
N = get_list_index(TVars, 1, TVar)
).
:- func get_list_index(list(T), hlds_class_argpos, T) = hlds_class_argpos.
get_list_index([], _, _) = _ :-
unexpected($pred, "element not found").
get_list_index([E | Es], N, X) =
( if X = E then
N
else
get_list_index(Es, N + 1, X)
).
:- pred constraints_are_identical(list(tvar)::in, tvarset::in,
list(prog_constraint)::in, list(tvar)::in, tvarset::in,
list(prog_constraint)::in) is semidet.
constraints_are_identical(OldVars0, OldVarSet, OldConstraints0,
Vars, VarSet, Constraints) :-
tvarset_merge_renaming(VarSet, OldVarSet, _, Renaming),
apply_variable_renaming_to_prog_constraint_list(Renaming, OldConstraints0,
OldConstraints1),
apply_variable_renaming_to_tvar_list(Renaming, OldVars0, OldVars),
map.from_corresponding_lists(OldVars, Vars, VarRenaming),
apply_variable_renaming_to_prog_constraint_list(VarRenaming,
OldConstraints1, OldConstraints),
OldConstraints = Constraints.
:- pred class_fundeps_are_identical(hlds_class_fundeps::in,
hlds_class_fundeps::in) is semidet.
class_fundeps_are_identical(OldFunDeps0, FunDeps0) :-
% Allow for the functional dependencies to be in a different order.
sort_and_remove_dups(OldFunDeps0, OldFunDeps),
sort_and_remove_dups(FunDeps0, FunDeps),
% The list elements we are comparing are sets; we rely on the fact that
% sets have a canonical representation.
OldFunDeps = FunDeps.
:- pred module_add_class_interface(sym_name::in, list(tvar)::in,
typeclass_status::in, maybe(item_mercury_status)::in,
need_qualifier::in, list(class_method)::in, list(maybe(pred_proc_id))::out,
module_info::in, module_info::out,
list(error_spec)::in, list(error_spec)::out) is det.
module_add_class_interface(ClassName, ClassParamVars, TypeClassStatus,
MaybeItemMercuryStatus, NeedQual, Methods, PredProcIds,
!ModuleInfo, !Specs) :-
list.filter(is_class_method_mode_item, Methods, ModeMethods,
PredOrFuncMethods),
some [!PPIds] (
add_class_pred_or_func_methods(ClassName, ClassParamVars,
MaybeItemMercuryStatus, TypeClassStatus, NeedQual,
PredOrFuncMethods, !:PPIds, !ModuleInfo, !Specs),
% Add the pred_or_func_mode decls. Since we have already added the
% predicate/function method decls, there should already be an entry in
% the predicate table corresponding to the mode item we are about to
% add. If not, report an error.
ItemNumber = -1,
list.foldl3(
add_class_pred_or_func_mode_method(ClassName, ClassParamVars,
ItemNumber, MaybeItemMercuryStatus, TypeClassStatus, NeedQual),
ModeMethods, !PPIds, !ModuleInfo, !Specs),
check_method_modes(Methods, !.PPIds, PredProcIds, !ModuleInfo, !Specs)
).
:- pred is_class_method_mode_item(class_method::in) is semidet.
is_class_method_mode_item(Method) :-
Method = method_pred_or_func_mode(_, _, _, _, _, _, _).
:- pred add_class_pred_or_func_mode_method(sym_name::in, list(tvar)::in,
int::in, maybe(item_mercury_status)::in, typeclass_status::in,
need_qualifier::in, class_method::in,
list(maybe(pred_proc_id))::in, list(maybe(pred_proc_id))::out,
module_info::in, module_info::out,
list(error_spec)::in, list(error_spec)::out) is det.
add_class_pred_or_func_mode_method(ClassName, ClassParamVars,
ItemNumber, MaybeItemMercuryStatus, TypeClassStatus, NeedQual, Method,
!PredProcIds, !ModuleInfo, !Specs) :-
(
Method = method_pred_or_func(_, _, _, _, _, _, _, _, _, _, _, _),
unexpected($pred, "pred_or_func method item")
;
Method = method_pred_or_func_mode(PredName, MaybePredOrFunc, Modes,
_WithInst, _MaybeDetism, _VarSet, Context)
),
module_info_get_predicate_table(!.ModuleInfo, PredTable),
PredArity = list.length(Modes) : int,
(
MaybePredOrFunc = no,
% The only way this could have happened now is if a `with_inst`
% annotation was not expanded.
unexpected($pred, "unexpanded `with_inst` annotation")
;
MaybePredOrFunc = yes(PredOrFunc)
),
predicate_table_lookup_pf_sym_arity(PredTable, is_fully_qualified,
PredOrFunc, PredName, PredArity, PredIds),
(
PredIds = [],
missing_pred_or_func_method_error(PredName, PredArity, PredOrFunc,
Context, !Specs)
;
PredIds = [HeadPredId | TailPredIds],
(
TailPredIds = [],
PredId = HeadPredId,
module_info_pred_info(!.ModuleInfo, PredId, PredInfo),
pred_info_get_markers(PredInfo, PredMarkers),
( if check_marker(PredMarkers, marker_class_method) then
module_add_class_method(ClassName, ClassParamVars,
ItemNumber, MaybeItemMercuryStatus, TypeClassStatus,
NeedQual, Method, PredProcId, !ModuleInfo, !Specs),
list.cons(PredProcId, !PredProcIds)
else
% XXX It may also be worth reporting that although there
% wasn't a matching class method, there was a matching
% predicate/function.
missing_pred_or_func_method_error(PredName, PredArity,
PredOrFunc, Context, !Specs)
)
;
TailPredIds = [_ | _],
% This shouldn't happen.
unexpected($pred, "multiple preds matching method mode")
)
).
:- pred add_class_pred_or_func_methods(sym_name::in, list(tvar)::in,
maybe(item_mercury_status)::in, typeclass_status::in, need_qualifier::in,
list(class_method)::in, list(maybe(pred_proc_id))::out,
module_info::in, module_info::out,
list(error_spec)::in, list(error_spec)::out) is det.
add_class_pred_or_func_methods(_, _, _, _, _, [], [], !ModuleInfo, !Specs).
add_class_pred_or_func_methods(ClassName, ClassParamVars,
MaybeItemMercuryStatus, TypeClassStatus, NeedQual, [Method | Methods],
[MaybePredProcId | MaybePredProcIds], !ModuleInfo, !Specs) :-
ItemNumber = -1,
module_add_class_method(ClassName, ClassParamVars,
ItemNumber, MaybeItemMercuryStatus, TypeClassStatus, NeedQual, Method,
MaybePredProcId, !ModuleInfo, !Specs),
add_class_pred_or_func_methods(ClassName, ClassParamVars,
MaybeItemMercuryStatus, TypeClassStatus, NeedQual, Methods,
MaybePredProcIds, !ModuleInfo, !Specs).
:- pred module_add_class_method(sym_name::in, list(tvar)::in,
int::in, maybe(item_mercury_status)::in, typeclass_status::in,
need_qualifier::in, class_method::in, maybe(pred_proc_id)::out,
module_info::in, module_info::out,
list(error_spec)::in, list(error_spec)::out) is det.
module_add_class_method(ClassName, ClassParamVars,
ItemNumber, MaybeItemMercuryStatus, TypeClassStatus, NeedQual, Method,
MaybePredIdProcId, !ModuleInfo, !Specs) :-
% XXX STATUS
TypeClassStatus = typeclass_status(OldImportStatus),
PredStatus = pred_status(OldImportStatus),
(
Method = method_pred_or_func(PredName, PredOrFunc, TypesAndModes,
WithType, WithInst, MaybeDetism, TypeVarSet, InstVarSet,
ExistQVars, Purity, Constraints0, Context),
% Any WithType and WithInst annotations should have been expanded
% and the type and/or inst put into TypesAndModes by equiv_type.m.
expect(unify(WithType, no), $pred, "WithType != no"),
expect(unify(WithInst, no), $pred, "WithInst != no"),
% XXX This setting of Origin looks suspicious.
Origin = origin_user(PredName),
% XXX kind inference:
% We set the kinds to `star' at the moment. This will be different
% when we have a kind system.
prog_type.var_list_to_type_list(map.init, ClassParamVars,
ClassParamTypes),
Constraints0 = constraints(UnivConstraints0, ExistConstraints),
UnivConstraints = [constraint(ClassName, ClassParamTypes)
| UnivConstraints0],
Constraints = constraints(UnivConstraints, ExistConstraints),
init_markers(Markers0),
add_marker(marker_class_method, Markers0, Markers),
module_add_pred_or_func(Origin, Context, ItemNumber,
MaybeItemMercuryStatus, PredStatus, NeedQual,
PredOrFunc, PredName, TypeVarSet, InstVarSet, ExistQVars,
TypesAndModes, Constraints, MaybeDetism, Purity, Markers,
MaybePredIdProcId, !ModuleInfo, !Specs)
;
Method = method_pred_or_func_mode(PredName, MaybePredOrFunc, Modes,
_WithInst, MaybeDet, VarSet, Context),
(
MaybePredOrFunc = yes(PredOrFunc),
module_add_mode(Context, ItemNumber,
MaybeItemMercuryStatus, PredStatus,
PredOrFunc, PredName, VarSet, Modes, MaybeDet,
is_a_class_method, PredIdProcId, !ModuleInfo, !Specs),
MaybePredIdProcId = yes(PredIdProcId)
;
MaybePredOrFunc = no,
% equiv_type.m should have either set the
% pred_or_func or removed the item from the list.
unexpected($pred, "no pred_or_func on mode declaration")
)
).
% Go through the list of class methods, looking for
% - functions without mode declarations: add a default mode
% - predicates without mode declarations: report an error
% - mode declarations with no determinism: report an error
%
:- pred check_method_modes(class_methods::in,
list(maybe(pred_proc_id))::in, list(maybe(pred_proc_id))::out,
module_info::in, module_info::out,
list(error_spec)::in, list(error_spec)::out) is det.
check_method_modes([], !PredProcIds, !ModuleInfo, !Specs).
check_method_modes([Method | Methods], !PredProcIds, !ModuleInfo, !Specs) :-
(
Method = method_pred_or_func(QualPredOrFuncName, PorF, TypesAndModes,
_, _, _, _, _, _, _, _, _),
(
QualPredOrFuncName = qualified(ModuleName, PredOrFuncName)
;
QualPredOrFuncName = unqualified(_),
% The class interface should be fully module qualified
% by the parser at the time it is read in.
unexpected($pred, "unqualified func")
),
list.length(TypesAndModes, PredArity),
module_info_get_predicate_table(!.ModuleInfo, PredTable),
predicate_table_lookup_pf_m_n_a(PredTable, is_fully_qualified,
PorF, ModuleName, PredOrFuncName, PredArity, PredIds),
(
PredIds = [PredId],
module_info_pred_info(!.ModuleInfo, PredId, PredInfo0),
(
PorF = pf_function,
maybe_add_default_func_mode(PredInfo0, PredInfo, MaybeProc),
(
MaybeProc = no
;
MaybeProc = yes(ProcId),
NewPredProc = yes(proc(PredId, ProcId)),
!:PredProcIds = [NewPredProc | !.PredProcIds],
module_info_set_pred_info(PredId, PredInfo, !ModuleInfo)
) ;
PorF = pf_predicate,
pred_info_get_proc_table(PredInfo0, Procs),
( if map.is_empty(Procs) then
pred_method_with_no_modes_error(PredInfo0, !Specs)
else
true
)
)
;
( PredIds = []
; PredIds = [_, _ | _]
),
unexpected($pred, "number of preds != 1")
)
;
Method = method_pred_or_func_mode(_, _, _, _, _, _, _)
),
check_method_modes(Methods, !PredProcIds, !ModuleInfo, !Specs).
%-----------------------------------------------------------------------------%
add_instance_defn(StatusItem, !ModuleInfo, !Specs) :-
StatusItem = ims_item(ItemMercuryStatus, ItemInstanceInfo),
ItemInstanceInfo = item_instance_info(ClassName, Types, OriginalTypes,
Constraints, InstanceBody0, VarSet, InstanceModuleName,
Context, _SeqNum),
item_mercury_status_to_instance_status(ItemMercuryStatus, InstanceStatus0),
(
InstanceBody0 = instance_body_abstract,
% XXX This can make the status abstract_imported even if the instance
% is NOT imported.
% When this is fixed, please undo the workaround for this bug
% in instance_used_modules in unused_imports.m.
instance_make_status_abstract(InstanceStatus0, InstanceStatus)
;
InstanceBody0 = instance_body_concrete(_),
InstanceStatus = InstanceStatus0
),
module_info_get_class_table(!.ModuleInfo, Classes),
module_info_get_instance_table(!.ModuleInfo, InstanceTable0),
list.length(Types, ClassArity),
ClassId = class_id(ClassName, ClassArity),
expand_bang_state_pairs_in_instance_body(InstanceBody0, InstanceBody),
( if map.search(Classes, ClassId, _) then
MaybeClassInterface = no,
map.init(ProofMap),
NewInstanceDefn = hlds_instance_defn(InstanceModuleName,
Types, OriginalTypes, InstanceStatus, Context, Constraints,
InstanceBody, MaybeClassInterface, VarSet, ProofMap),
map.lookup(InstanceTable0, ClassId, OldInstanceDefns),
check_for_overlapping_instances(NewInstanceDefn, OldInstanceDefns,
ClassId, !Specs),
check_instance_compatibility(NewInstanceDefn, OldInstanceDefns,
ClassId, !Specs),
map.det_update(ClassId, [NewInstanceDefn | OldInstanceDefns],
InstanceTable0, InstanceTable),
module_info_set_instance_table(InstanceTable, !ModuleInfo)
else
undefined_type_class_error(ClassName, ClassArity, Context,
"instance declaration", !Specs)
).
:- pred check_for_overlapping_instances(hlds_instance_defn::in,
list(hlds_instance_defn)::in, class_id::in,
list(error_spec)::in, list(error_spec)::out) is det.
check_for_overlapping_instances(NewInstanceDefn, OtherInstanceDefns,
ClassId, !Specs) :-
NewInstanceDefn = hlds_instance_defn(_, NewTypes, _, _, NewContext,
_, NewInstanceBody, _, NewTVarSet, _),
( if
NewInstanceBody = instance_body_concrete(_) % XXX
then
report_any_overlapping_instance_declarations(ClassId,
NewTypes, NewTVarSet, NewContext, OtherInstanceDefns, !Specs)
else
true
).
:- pred report_any_overlapping_instance_declarations(class_id::in,
list(mer_type)::in, tvarset::in, prog_context::in,
list(hlds_instance_defn)::in,
list(error_spec)::in, list(error_spec)::out) is det.
report_any_overlapping_instance_declarations(_, _, _, _, [], !Specs).
report_any_overlapping_instance_declarations(ClassId,
NewTypes, NewTVarSet, NewContext,
[OtherInstanceDefn | OtherInstanceDefns], !Specs) :-
OtherInstanceDefn = hlds_instance_defn(_, OtherTypes, _, _, OtherContext,
_, OtherInstanceBody, _, OtherTVarSet, _),
( if
OtherInstanceBody = instance_body_concrete(_), % XXX
tvarset_merge_renaming(NewTVarSet, OtherTVarSet, _MergedTVarSet,
Renaming),
apply_variable_renaming_to_type_list(Renaming, OtherTypes,
NewOtherTypes),
type_list_subsumes(NewTypes, NewOtherTypes, _)
then
ClassId = class_id(ClassName, ClassArity),
% XXX STATUS Multiply defined if type_list_subsumes in BOTH directions.
NewPieces = [words("Error: multiply defined (or overlapping)"),
words("instance declarations for class"),
qual_sym_name_and_arity(sym_name_arity(ClassName, ClassArity)),
suffix("."), nl],
NewMsg = simple_msg(NewContext, [always(NewPieces)]),
OtherPieces = [words("Previous instance declaration was here.")],
OtherMsg = error_msg(yes(OtherContext), treat_as_first, 0,
[always(OtherPieces)]),
Spec = error_spec(severity_error, phase_parse_tree_to_hlds,
[NewMsg, OtherMsg]),
!:Specs = [Spec | !.Specs]
else
true
),
% Maybe we shouldn't recurse if we generated an error above,
% but triply-defined instances are so rare that it doesn't much matter,
% and in some even more rare cases, the extra info may be useful.
report_any_overlapping_instance_declarations(ClassId,
NewTypes, NewTVarSet, NewContext, OtherInstanceDefns, !Specs).
% If two instance declarations are about the same type, then one must be
% the abstract declaration and the other the concrete definition.
% The two must be compatible, i.e. their constraints must be identical.
% If they are not, then generate an error message.
%
:- pred check_instance_compatibility(hlds_instance_defn::in,
list(hlds_instance_defn)::in, class_id::in,
list(error_spec)::in, list(error_spec)::out) is det.
check_instance_compatibility(InstanceDefn, InstanceDefns, ClassId, !Specs) :-
list.filter(same_type_hlds_instance_defn(InstanceDefn),
InstanceDefns, EquivInstanceDefns),
list.foldl(check_instance_constraints(InstanceDefn, ClassId),
EquivInstanceDefns, !Specs).
:- pred check_instance_constraints(hlds_instance_defn::in,
class_id::in, hlds_instance_defn::in,
list(error_spec)::in, list(error_spec)::out) is det.
check_instance_constraints(InstanceDefnA, ClassId, InstanceDefnB, !Specs) :-
type_vars_list(InstanceDefnA ^ instdefn_types, TVarsA),
TVarSetA = InstanceDefnA ^ instdefn_tvarset,
ConstraintsA = InstanceDefnA ^ instdefn_constraints,
type_vars_list(InstanceDefnB ^ instdefn_types, TVarsB),
TVarSetB = InstanceDefnB ^ instdefn_tvarset,
ConstraintsB = InstanceDefnB ^ instdefn_constraints,
( if
constraints_are_identical(TVarsA, TVarSetA, ConstraintsA,
TVarsB, TVarSetB, ConstraintsB)
then
true
else
ClassId = class_id(ClassName, ClassArity),
ContextA = InstanceDefnA ^ instdefn_context,
PiecesA = [words("In instance declaration for class "),
qual_sym_name_and_arity(sym_name_arity(ClassName, ClassArity)), nl,
words("instance constraints are incompatible with")],
MsgA = simple_msg(ContextA, [always(PiecesA)]),
ContextB = InstanceDefnB ^ instdefn_context,
PiecesB = [words("instance constraints here.")],
MsgB = simple_msg(ContextB, [always(PiecesB)]),
Spec = error_spec(severity_error,
phase_parse_tree_to_hlds, [MsgA, MsgB]),
!:Specs = [Spec | !.Specs]
).
% Do two hlds_instance_defn refer to the same type?
% e.g. "instance tc(f(T))" compares equal to "instance tc(f(U))"
%
% Note we don't check that the constraints of the declarations are the
% same.
%
:- pred same_type_hlds_instance_defn(hlds_instance_defn::in,
hlds_instance_defn::in) is semidet.
same_type_hlds_instance_defn(InstanceDefnA, InstanceDefnB) :-
TypesA = InstanceDefnA ^ instdefn_types,
TypesB0 = InstanceDefnB ^ instdefn_types,
VarSetA = InstanceDefnA ^ instdefn_tvarset,
VarSetB = InstanceDefnB ^ instdefn_tvarset,
% Rename the two lists of types apart.
tvarset_merge_renaming(VarSetA, VarSetB, _NewVarSet, RenameApart),
apply_variable_renaming_to_type_list(RenameApart, TypesB0, TypesB1),
type_vars_list(TypesA, TVarsA),
type_vars_list(TypesB1, TVarsB),
% If the lengths are different they can't be the same type.
list.length(TVarsA, NumTVars),
list.length(TVarsB, NumTVars),
map.from_corresponding_lists(TVarsB, TVarsA, Renaming),
apply_variable_renaming_to_type_list(Renaming, TypesB1, TypesB),
TypesA = TypesB.
do_produce_instance_method_clauses(InstanceProcDefn, PredOrFunc, PredArity,
ArgTypes, Markers, Context, InstanceStatus, ClausesInfo,
!TVarSet, !ModuleInfo, !QualInfo, !Specs) :-
(
% Handle the `pred(<MethodName>/<Arity>) is <ImplName>' syntax.
InstanceProcDefn = instance_proc_def_name(InstancePredName),
% Add the body of the introduced pred.
% First the goal info, ...
goal_info_init(GoalInfo0),
goal_info_set_context(Context, GoalInfo0, GoalInfo1),
set_of_var.list_to_set(HeadVars, NonLocals),
goal_info_set_nonlocals(NonLocals, GoalInfo1, GoalInfo2),
( if check_marker(Markers, marker_is_impure) then
goal_info_set_purity(purity_impure, GoalInfo2, GoalInfo)
else if check_marker(Markers, marker_is_semipure) then
goal_info_set_purity(purity_semipure, GoalInfo2, GoalInfo)
else
GoalInfo = GoalInfo2
),
% ... and then the goal itself.
varset.init(VarSet0),
make_n_fresh_vars("HeadVar__", PredArity, HeadVars, VarSet0, VarSet),
construct_pred_or_func_call(invalid_pred_id, PredOrFunc,
InstancePredName, HeadVars, GoalInfo, IntroducedGoal, !QualInfo),
IntroducedClause = clause(all_modes, IntroducedGoal, impl_lang_mercury,
Context, []),
map.init(TVarNameMap),
vartypes_from_corresponding_lists(HeadVars, ArgTypes, VarTypes),
HeadVarVec = proc_arg_vector_init(PredOrFunc, HeadVars),
set_clause_list([IntroducedClause], ClausesRep),
rtti_varmaps_init(RttiVarMaps),
HasForeignClauses = no,
HadSyntaxErrors = no,
ClausesInfo = clauses_info(VarSet, TVarNameMap, VarTypes, VarTypes,
HeadVarVec, ClausesRep, init_clause_item_numbers_comp_gen,
RttiVarMaps, HasForeignClauses, HadSyntaxErrors)
;
% Handle the arbitrary clauses syntax.
InstanceProcDefn = instance_proc_def_clauses(InstanceClauses),
clauses_info_init(PredOrFunc, PredArity,
init_clause_item_numbers_comp_gen, ClausesInfo0),
list.foldl5(
produce_instance_method_clause(PredOrFunc, Context,
InstanceStatus),
InstanceClauses, !TVarSet, !ModuleInfo, !QualInfo,
ClausesInfo0, ClausesInfo, !Specs)
).
:- pred produce_instance_method_clause(pred_or_func::in,
prog_context::in, instance_status::in, item_clause_info::in,
tvarset::in, tvarset::out, module_info::in, module_info::out,
qual_info::in, qual_info::out, clauses_info::in, clauses_info::out,
list(error_spec)::in, list(error_spec)::out) is det.
produce_instance_method_clause(PredOrFunc, Context, InstanceStatus,
InstanceClause, TVarSet0, TVarSet, !ModuleInfo, !QualInfo,
!ClausesInfo, !Specs) :-
InstanceClause = item_clause_info(PredName, ClausePredOrFunc, HeadTerms0,
_Origin, CVarSet, MaybeBodyGoal, _ClauseContext, _SeqNum),
% XXX Can this ever fail? If yes, we should generate an error message
% instead of aborting.
expect(unify(PredOrFunc, ClausePredOrFunc), $pred, "PredOrFunc mismatch"),
( if
illegal_state_var_func_result(PredOrFunc, HeadTerms0, StateVar,
StateVarContext)
then
TVarSet = TVarSet0,
report_illegal_func_svar_result(StateVarContext, CVarSet, StateVar,
!Specs),
!:Specs = get_any_errors1(MaybeBodyGoal) ++ !.Specs
else
(
MaybeBodyGoal = error1(BodyGoalSpecs),
TVarSet = TVarSet0,
!:Specs = BodyGoalSpecs ++ !.Specs
;
MaybeBodyGoal = ok1(BodyGoal),
expand_bang_state_pairs_in_terms(HeadTerms0, HeadTerms),
PredArity = list.length(HeadTerms),
adjust_func_arity(PredOrFunc, Arity, PredArity),
% AllProcIds is only used when the predicate has foreign procs,
% which the instance method pred should not have, so this
% dummy value should be ok.
AllProcIds = [],
GoalType = goal_type_none, % goal is not a promise
% XXX STATUS
InstanceStatus = instance_status(OldImportStatus),
PredStatus = pred_status(OldImportStatus),
clauses_info_add_clause(all_modes, AllProcIds, CVarSet, TVarSet0,
HeadTerms, BodyGoal, Context, no, PredStatus, PredOrFunc,
Arity, GoalType, Goal, VarSet, TVarSet, Warnings,
!ClausesInfo, !ModuleInfo, !QualInfo, !Specs),
SimpleCallId = simple_call_id(PredOrFunc, PredName, Arity),
% Warn about singleton variables.
warn_singletons(!.ModuleInfo, SimpleCallId, VarSet, Goal, !Specs),
% Warn about variables with overlapping scopes.
add_quant_warnings(SimpleCallId, VarSet, Warnings, !Specs)
)
).
:- pred pred_method_with_no_modes_error(pred_info::in,
list(error_spec)::in, list(error_spec)::out) is det.
pred_method_with_no_modes_error(PredInfo, !Specs) :-
pred_info_get_context(PredInfo, Context),
ModuleName = pred_info_module(PredInfo),
PredName = pred_info_name(PredInfo),
Arity = pred_info_orig_arity(PredInfo),
Pieces = [words("Error: no mode declaration"),
words("for type class method predicate"),
qual_sym_name_and_arity(
sym_name_arity(qualified(ModuleName, PredName), Arity)),
suffix("."), nl],
Msg = simple_msg(Context, [always(Pieces)]),
Spec = error_spec(severity_error, phase_parse_tree_to_hlds, [Msg]),
!:Specs = [Spec | !.Specs].
:- pred undefined_type_class_error(sym_name::in, arity::in, prog_context::in,
string::in, list(error_spec)::in, list(error_spec)::out) is det.
undefined_type_class_error(ClassName, ClassArity, Context, Description,
!Specs) :-
Pieces = [words("Error:"), words(Description), words("for"),
qual_sym_name_and_arity(sym_name_arity(ClassName, ClassArity)),
words("without corresponding"), decl("typeclass"),
words("declaration."), nl],
Msg = simple_msg(Context, [always(Pieces)]),
Spec = error_spec(severity_error, phase_parse_tree_to_hlds, [Msg]),
!:Specs = [Spec | !.Specs].
:- pred missing_pred_or_func_method_error(sym_name::in, arity::in,
pred_or_func::in, prog_context::in,
list(error_spec)::in, list(error_spec)::out) is det.
missing_pred_or_func_method_error(MethodName, MethodArity, PredOrFunc,
Context, !Specs) :-
Pieces = [words("Error: mode declaration for type class method"),
qual_sym_name_and_arity(sym_name_arity(MethodName, MethodArity)),
words("without corresponding"), p_or_f(PredOrFunc),
words("method declaration."), nl],
Msg = simple_msg(Context, [always(Pieces)]),
Spec = error_spec(severity_error, phase_parse_tree_to_hlds, [Msg]),
!:Specs = [Spec | !.Specs].
%-----------------------------------------------------------------------------%
:- end_module hlds.make_hlds.add_class.
%-----------------------------------------------------------------------------%