TypeSpec best_candidate_return_type;
SessionReportPrinter lambda_conv_msgs;
- ReportPrinter prev_recorder;
public OverloadResolver (IList<MemberSpec> members, Restrictions restrictions, Location loc)
: this (members, null, restrictions, loc)
ms = ms.MakeGenericMethod (ec, type_arguments.Arguments);
} else {
- // TODO: It should not be here (we don't know yet whether any argument is lambda) but
- // for now it simplifies things. I should probably add a callback to ResolveContext
+ //
+ // Deploy custom error reporting for infered anonymous expression or lambda methods. When
+ // probing lambda methods keep all errors reported in separate set and once we are done and no best
+ // candidate was found use the set to report more details about what was wrong with lambda body.
+ // The general idea is to distinguish between code errors and errors caused by
+ // trial-and-error type inference
+ //
if (lambda_conv_msgs == null) {
- lambda_conv_msgs = new SessionReportPrinter ();
- prev_recorder = ec.Report.SetPrinter (lambda_conv_msgs);
+ for (int i = 0; i < arg_count; i++) {
+ Argument a = arguments[i];
+ if (a == null)
+ continue;
+
+ var am = a.Expr as AnonymousMethodExpression;
+ if (am != null) {
+ if (lambda_conv_msgs == null)
+ lambda_conv_msgs = new SessionReportPrinter ();
+
+ am.TypeInferenceReportPrinter = lambda_conv_msgs;
+ }
+ }
}
var ti = new TypeInference (arguments);
TypeSpec[] i_args = ti.InferMethodArguments (ec, ms);
- lambda_conv_msgs.EndSession ();
if (i_args == null)
return ti.InferenceScore - 20000;
if (argument.Type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (restrictions & Restrictions.CovariantDelegate) == 0)
return -1;
- //
- // Deploy custom error reporting for lambda methods. When probing lambda methods
- // keep all errors reported in separate set and once we are done and no best
- // candidate was found, this set is used to report more details about what was wrong
- // with lambda body
- //
- if (argument.Expr.Type == InternalType.AnonymousMethod) {
- if (lambda_conv_msgs == null) {
- lambda_conv_msgs = new SessionReportPrinter ();
- prev_recorder = ec.Report.SetPrinter (lambda_conv_msgs);
- }
- }
-
//
// Use implicit conversion in all modes to return same candidates when the expression
// is used as argument or delegate conversion
//
if (!Convert.ImplicitConversionExists (ec, argument.Expr, parameter)) {
- if (lambda_conv_msgs != null) {
- lambda_conv_msgs.EndSession ();
- }
-
return 2;
}
}
bool error_mode = false;
MemberSpec invocable_member = null;
- // Be careful, cannot return until error reporter is restored
while (true) {
best_candidate = null;
best_candidate_rate = int.MaxValue;
var type_members = members;
- try {
+ do {
+ for (int i = 0; i < type_members.Count; ++i) {
+ var member = type_members[i];
- do {
- for (int i = 0; i < type_members.Count; ++i) {
- var member = type_members[i];
+ //
+ // Methods in a base class are not candidates if any method in a derived
+ // class is applicable
+ //
+ if ((member.Modifiers & Modifiers.OVERRIDE) != 0)
+ continue;
+ if (!error_mode) {
+ if (!member.IsAccessible (rc))
+ continue;
+
+ if (rc.IsRuntimeBinder && !member.DeclaringType.IsAccessible (rc))
+ continue;
+
+ if ((member.Modifiers & (Modifiers.PROTECTED | Modifiers.STATIC)) == Modifiers.PROTECTED &&
+ instance_qualifier != null && !instance_qualifier.CheckProtectedMemberAccess (rc, member)) {
+ continue;
+ }
+ }
+
+ IParametersMember pm = member as IParametersMember;
+ if (pm == null) {
//
- // Methods in a base class are not candidates if any method in a derived
- // class is applicable
+ // Will use it later to report ambiguity between best method and invocable member
//
- if ((member.Modifiers & Modifiers.OVERRIDE) != 0)
- continue;
+ if (Invocation.IsMemberInvocable (member))
+ invocable_member = member;
- if (!error_mode) {
- if (!member.IsAccessible (rc))
- continue;
+ continue;
+ }
- if (rc.IsRuntimeBinder && !member.DeclaringType.IsAccessible (rc))
- continue;
+ //
+ // Overload resolution is looking for base member but using parameter names
+ // and default values from the closest member. That means to do expensive lookup
+ // for the closest override for virtual or abstract members
+ //
+ if ((member.Modifiers & (Modifiers.VIRTUAL | Modifiers.ABSTRACT)) != 0) {
+ var override_params = base_provider.GetOverrideMemberParameters (member);
+ if (override_params != null)
+ pm = override_params;
+ }
+
+ //
+ // Check if the member candidate is applicable
+ //
+ bool params_expanded_form = false;
+ bool dynamic_argument = false;
+ TypeSpec rt = pm.MemberType;
+ int candidate_rate = IsApplicable (rc, ref candidate_args, args_count, ref member, pm, ref params_expanded_form, ref dynamic_argument, ref rt);
- if ((member.Modifiers & (Modifiers.PROTECTED | Modifiers.STATIC)) == Modifiers.PROTECTED &&
- instance_qualifier != null && !instance_qualifier.CheckProtectedMemberAccess (rc, member)) {
+ if (lambda_conv_msgs != null)
+ lambda_conv_msgs.EndSession ();
+
+ //
+ // How does it score compare to others
+ //
+ if (candidate_rate < best_candidate_rate) {
+ best_candidate_rate = candidate_rate;
+ best_candidate = member;
+ best_candidate_args = candidate_args;
+ best_candidate_params = params_expanded_form;
+ best_candidate_dynamic = dynamic_argument;
+ best_parameter_member = pm;
+ best_candidate_return_type = rt;
+ } else if (candidate_rate == 0) {
+ //
+ // The member look is done per type for most operations but sometimes
+ // it's not possible like for binary operators overload because they
+ // are unioned between 2 sides
+ //
+ if ((restrictions & Restrictions.BaseMembersIncluded) != 0) {
+ if (TypeSpec.IsBaseClass (best_candidate.DeclaringType, member.DeclaringType, true))
continue;
- }
}
- IParametersMember pm = member as IParametersMember;
- if (pm == null) {
+ bool is_better;
+ if (best_candidate.DeclaringType.IsInterface && member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
+ //
+ // We pack all interface members into top level type which makes the overload resolution
+ // more complicated for interfaces. We compensate it by removing methods with same
+ // signature when building the cache hence this path should not really be hit often
+ //
+ // Example:
+ // interface IA { void Foo (int arg); }
+ // interface IB : IA { void Foo (params int[] args); }
//
- // Will use it later to report ambiguity between best method and invocable member
+ // IB::Foo is the best overload when calling IB.Foo (1)
//
- if (Invocation.IsMemberInvocable (member))
- invocable_member = member;
+ is_better = true;
+ if (ambiguous_candidates != null) {
+ foreach (var amb_cand in ambiguous_candidates) {
+ if (member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
+ continue;
+ }
- continue;
- }
+ is_better = false;
+ break;
+ }
- //
- // Overload resolution is looking for base member but using parameter names
- // and default values from the closest member. That means to do expensive lookup
- // for the closest override for virtual or abstract members
- //
- if ((member.Modifiers & (Modifiers.VIRTUAL | Modifiers.ABSTRACT)) != 0) {
- var override_params = base_provider.GetOverrideMemberParameters (member);
- if (override_params != null)
- pm = override_params;
+ if (is_better)
+ ambiguous_candidates = null;
+ }
+ } else {
+ // Is the new candidate better
+ is_better = BetterFunction (rc, candidate_args, member, pm.Parameters, params_expanded_form, best_candidate, best_parameter_member.Parameters, best_candidate_params);
}
- //
- // Check if the member candidate is applicable
- //
- bool params_expanded_form = false;
- bool dynamic_argument = false;
- TypeSpec rt = pm.MemberType;
- int candidate_rate = IsApplicable (rc, ref candidate_args, args_count, ref member, pm, ref params_expanded_form, ref dynamic_argument, ref rt);
-
- //
- // How does it score compare to others
- //
- if (candidate_rate < best_candidate_rate) {
- best_candidate_rate = candidate_rate;
+ if (is_better) {
best_candidate = member;
best_candidate_args = candidate_args;
best_candidate_params = params_expanded_form;
best_candidate_dynamic = dynamic_argument;
best_parameter_member = pm;
best_candidate_return_type = rt;
- } else if (candidate_rate == 0) {
- //
- // The member look is done per type for most operations but sometimes
- // it's not possible like for binary operators overload because they
- // are unioned between 2 sides
- //
- if ((restrictions & Restrictions.BaseMembersIncluded) != 0) {
- if (TypeSpec.IsBaseClass (best_candidate.DeclaringType, member.DeclaringType, true))
- continue;
- }
-
- bool is_better;
- if (best_candidate.DeclaringType.IsInterface && member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
- //
- // We pack all interface members into top level type which makes the overload resolution
- // more complicated for interfaces. We compensate it by removing methods with same
- // signature when building the cache hence this path should not really be hit often
- //
- // Example:
- // interface IA { void Foo (int arg); }
- // interface IB : IA { void Foo (params int[] args); }
- //
- // IB::Foo is the best overload when calling IB.Foo (1)
- //
- is_better = true;
- if (ambiguous_candidates != null) {
- foreach (var amb_cand in ambiguous_candidates) {
- if (member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
- continue;
- }
-
- is_better = false;
- break;
- }
-
- if (is_better)
- ambiguous_candidates = null;
- }
- } else {
- // Is the new candidate better
- is_better = BetterFunction (rc, candidate_args, member, pm.Parameters, params_expanded_form, best_candidate, best_parameter_member.Parameters, best_candidate_params);
- }
+ } else {
+ // It's not better but any other found later could be but we are not sure yet
+ if (ambiguous_candidates == null)
+ ambiguous_candidates = new List<AmbiguousCandidate> ();
- if (is_better) {
- best_candidate = member;
- best_candidate_args = candidate_args;
- best_candidate_params = params_expanded_form;
- best_candidate_dynamic = dynamic_argument;
- best_parameter_member = pm;
- best_candidate_return_type = rt;
- } else {
- // It's not better but any other found later could be but we are not sure yet
- if (ambiguous_candidates == null)
- ambiguous_candidates = new List<AmbiguousCandidate> ();
-
- ambiguous_candidates.Add (new AmbiguousCandidate (member, pm.Parameters, params_expanded_form));
- }
+ ambiguous_candidates.Add (new AmbiguousCandidate (member, pm.Parameters, params_expanded_form));
}
-
- // Restore expanded arguments
- if (candidate_args != args)
- candidate_args = args;
}
- } while (best_candidate_rate != 0 && (type_members = base_provider.GetBaseMembers (type_members[0].DeclaringType.BaseType)) != null);
- } finally {
- if (prev_recorder != null)
- rc.Report.SetPrinter (prev_recorder);
- }
+
+ // Restore expanded arguments
+ if (candidate_args != args)
+ candidate_args = args;
+ }
+ } while (best_candidate_rate != 0 && (type_members = base_provider.GetBaseMembers (type_members[0].DeclaringType.BaseType)) != null);
//
// We've found exact match
return;
}
- if (lambda_conv_msgs != null) {
- if (lambda_conv_msgs.Merge (rc.Report.Printer))
- return;
+ if (lambda_conv_msgs != null && lambda_conv_msgs.Merge (rc.Report.Printer)) {
+ return;
}
projects / mono.git / commitdiff