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Check equality constraints when checking whether a constraint is satisfied (#2294)

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Add checking that a type only satisfies a constraint if it satisfies all of that constraint's equality and rewrite constraints.

Enforce the rule that `=` must be used in impls when specifying associated constant values rather than `==`.

Turn off the pre-#2173 single-step equality behavior. This is getting somewhat ahead of the approved design, but it's a one-line change to restore the old behavior.

Fix `CARBON_CHECK` to handle top-level `,`s in its argument, such as may happen in template argument lists, as this change introduces such a check.
This commit is contained in:
Richard Smith
2022-10-17 22:07:19 -07:00
committed by GitHub
parent 8ee0ecec94
commit 4b679510e7
43 changed files with 443 additions and 200 deletions
Download Patch File Download Diff File Expand all files Collapse all files
common/check.h
+8 -8
View File
@@ -21,18 +21,18 @@ namespace Carbon {
//
// For example:
// CARBON_CHECK(is_valid) << "Data is not valid!";
#define CARBON_CHECK(condition) \
(condition) ? (void)0 \
: CARBON_RAW_EXITING_STREAM() \
<< "CHECK failure at " << __FILE__ << ":" << __LINE__ \
<< ": " #condition \
<< Carbon::Internal::ExitingStream::AddSeparator()
#define CARBON_CHECK(...) \
(__VA_ARGS__) ? (void)0 \
: CARBON_RAW_EXITING_STREAM() \
<< "CHECK failure at " << __FILE__ << ":" << __LINE__ \
<< ": " #__VA_ARGS__ \
<< Carbon::Internal::ExitingStream::AddSeparator()
// DCHECK calls CHECK in debug mode, and does nothing otherwise.
#ifndef NDEBUG
#define CARBON_DCHECK(condition) CARBON_CHECK(condition)
#define CARBON_DCHECK(...) CARBON_CHECK(__VA_ARGS__)
#else
#define CARBON_DCHECK(condition) CARBON_CHECK(true || (condition))
#define CARBON_DCHECK(...) CARBON_CHECK(true || (__VA_ARGS__))
#endif
// This is similar to CHECK, but is unconditional. Writing CARBON_FATAL() is
explorer/data/prelude.carbon
+15 -3
View File
@@ -18,9 +18,21 @@ interface ImplicitAs(T:! Type) {
extends As(T);
}
// Every type implicitly converts to itself.
impl forall [T:! Type] T as ImplicitAs(T) {
fn Convert[me: Self]() -> T { return me; }
// TODO: Should we just use an intrinsic for this?
interface __EqualConverter {
let T:! Type;
fn Convert(t: T) -> Self;
}
fn __EqualConvert[T:! Type](t: T, U:! __EqualConverter where .T = T) -> U {
return U.Convert(t);
}
impl forall [U:! Type] U as __EqualConverter where .T = U {
fn Convert(u: U) -> U { return u; }
}
// Every type implicitly converts to single-step-equal types.
impl forall [T:! Type, U:! Type where .Self == T] T as ImplicitAs(U) {
fn Convert[me: Self]() -> U { return __EqualConvert(me, U); }
}
// TODO: Simplify this once we have variadics.
explorer/interpreter/impl_scope.cpp
+34 -1
View File
@@ -103,7 +103,34 @@ auto ImplScope::Resolve(Nonnull<const Value*> constraint_type,
source_loc, type_checker));
witnesses.push_back(result);
}
// TODO: Check satisfaction of same-type constraints.
// Check that all equality constraints are satisfied in this scope.
if (llvm::ArrayRef<EqualityConstraint> equals =
constraint->equality_constraints();
!equals.empty()) {
std::optional<Nonnull<const Witness*>> witness;
if (constraint->self_binding()->impl_binding()) {
witness = type_checker.MakeConstraintWitness(*constraint, witnesses,
source_loc);
}
Bindings local_bindings = bindings;
local_bindings.Add(constraint->self_binding(), impl_type, witness);
SingleStepEqualityContext equality_ctx(this);
for (auto& equal : equals) {
auto it = equal.values.begin();
Nonnull<const Value*> first =
type_checker.Substitute(local_bindings, *it++);
for (; it != equal.values.end(); ++it) {
Nonnull<const Value*> current =
type_checker.Substitute(local_bindings, *it);
if (!ValueEqual(first, current, &equality_ctx)) {
return ProgramError(source_loc)
<< "constraint requires that " << *first
<< " == " << *current << ", which is not known to be true";
}
}
}
}
return type_checker.MakeConstraintWitness(*constraint, std::move(witnesses),
source_loc);
}
@@ -233,4 +260,10 @@ void ImplScope::Print(llvm::raw_ostream& out) const {
}
}
auto SingleStepEqualityContext::VisitEqualValues(
Nonnull<const Value*> value,
llvm::function_ref<bool(Nonnull<const Value*>)> visitor) const -> bool {
return impl_scope_->VisitEqualValues(value, visitor);
}
} // namespace Carbon
explorer/interpreter/impl_scope.h
+20
View File
@@ -153,6 +153,26 @@ class ImplScope {
std::vector<Nonnull<const ImplScope*>> parent_scopes_;
};
// An equality context that considers two values to be equal if they are a
// single step apart according to an equality constraint in the given impl
// scope.
struct SingleStepEqualityContext : public EqualityContext {
public:
SingleStepEqualityContext(Nonnull<const ImplScope*> impl_scope)
: impl_scope_(impl_scope) {}
// Visits the values that are equal to the given value and a single step away
// according to an equality constraint that is in the given impl scope. Stops
// and returns `false` if the visitor returns `false`, otherwise returns
// `true`.
auto VisitEqualValues(Nonnull<const Value*> value,
llvm::function_ref<bool(Nonnull<const Value*>)> visitor)
const -> bool override;
private:
Nonnull<const ImplScope*> impl_scope_;
};
} // namespace Carbon
#endif // CARBON_EXPLORER_INTERPRETER_IMPL_SCOPE_H_
explorer/interpreter/interpreter.cpp
+56 -26
View File
@@ -538,35 +538,47 @@ auto Interpreter::EvalRecursively(std::unique_ptr<Action> action)
auto Interpreter::EvalAssociatedConstant(
Nonnull<const AssociatedConstant*> assoc, SourceLocation source_loc)
-> ErrorOr<Nonnull<const Value*>> {
// Find the witness.
// Instantiate the associated constant.
CARBON_ASSIGN_OR_RETURN(Nonnull<const Value*> base,
InstantiateType(&assoc->base(), source_loc));
CARBON_ASSIGN_OR_RETURN(Nonnull<const Value*> interface,
InstantiateType(&assoc->interface(), source_loc));
CARBON_ASSIGN_OR_RETURN(Nonnull<const Witness*> witness,
InstantiateWitness(&assoc->witness()));
if (!isa<ImplWitness>(witness)) {
Nonnull<const AssociatedConstant*> instantiated_assoc =
arena_->New<AssociatedConstant>(base, cast<InterfaceType>(interface),
&assoc->constant(), witness);
auto* impl_witness = dyn_cast<ImplWitness>(witness);
if (!impl_witness) {
CARBON_CHECK(phase() == Phase::CompileTime)
<< "symbolic witnesses should only be formed at compile time";
return ProgramError(source_loc)
<< "value of associated constant " << *assoc << " is not known";
return instantiated_assoc;
}
auto& impl_witness = cast<ImplWitness>(*witness);
// We have an impl. Extract the value from it.
Nonnull<const ConstraintType*> constraint =
impl_witness.declaration().constraint_type();
impl_witness->declaration().constraint_type();
std::optional<Nonnull<const Value*>> result;
constraint->VisitEqualValues(assoc, [&](Nonnull<const Value*> equal_value) {
// TODO: The value might depend on the parameters of the impl. We need to
// substitute impl_witness.type_args() into the value or constraint.
if (isa<AssociatedConstant>(equal_value)) {
return true;
}
// TODO: This makes an arbitrary choice if there's more than one equal
// value. It's not clear how to handle that case.
result = equal_value;
return false;
});
// TODO: We should pick the value from the rewrite constraint, not some other
// equality constraint that happens to be in the impl's constraint type.
constraint->VisitEqualValues(instantiated_assoc,
[&](Nonnull<const Value*> equal_value) {
// TODO: The value might depend on the
// parameters of the impl. We need to
// substitute impl_witness->type_args() into
// the value or constraint.
if (isa<AssociatedConstant>(equal_value)) {
return true;
}
result = equal_value;
return false;
});
if (!result) {
CARBON_FATAL() << impl_witness.declaration() << " with constraint "
CARBON_FATAL() << impl_witness->declaration() << " with constraint "
<< *constraint
<< " is missing value for associated constant " << *assoc;
<< " is missing value for associated constant "
<< *instantiated_assoc;
}
return *result;
}
@@ -585,6 +597,14 @@ auto Interpreter::InstantiateType(Nonnull<const Value*> type,
}
return value;
}
case Value::Kind::InterfaceType: {
const auto& interface_type = cast<InterfaceType>(*type);
CARBON_ASSIGN_OR_RETURN(
Nonnull<const Bindings*> bindings,
InstantiateBindings(&interface_type.bindings(), source_loc));
return arena_->New<InterfaceType>(&interface_type.declaration(),
bindings);
}
case Value::Kind::NominalClassType: {
const auto& class_type = cast<NominalClassType>(*type);
CARBON_ASSIGN_OR_RETURN(
@@ -603,7 +623,7 @@ auto Interpreter::InstantiateType(Nonnull<const Value*> type,
CARBON_ASSIGN_OR_RETURN(
Nonnull<const Value*> type_value,
EvalAssociatedConstant(cast<AssociatedConstant>(type), source_loc));
return InstantiateType(type_value, source_loc);
return type_value;
}
default:
return type;
@@ -715,9 +735,12 @@ auto Interpreter::Convert(Nonnull<const Value*> value,
InstantiateType(destination_type, source_loc));
return arena_->New<NominalClassValue>(inst_dest, value);
}
default:
CARBON_FATAL() << "Can't convert value " << *value << " to type "
<< *destination_type;
default: {
CARBON_CHECK(IsValueKindDependent(destination_type))
<< "Can't convert value " << *value << " to type "
<< *destination_type;
return value;
}
}
}
case Value::Kind::StructType: {
@@ -747,9 +770,12 @@ auto Interpreter::Convert(Nonnull<const Value*> value,
&array_type.element_type());
break;
}
default:
CARBON_FATAL() << "Can't convert value " << *value << " to type "
<< *destination_type;
default: {
CARBON_CHECK(IsValueKindDependent(destination_type))
<< "Can't convert value " << *value << " to type "
<< *destination_type;
return value;
}
}
CARBON_CHECK(tuple->elements().size() ==
destination_element_types.size());
@@ -767,6 +793,10 @@ auto Interpreter::Convert(Nonnull<const Value*> value,
CARBON_ASSIGN_OR_RETURN(
Nonnull<const Value*> value,
EvalAssociatedConstant(cast<AssociatedConstant>(value), source_loc));
if (isa<AssociatedConstant>(value)) {
return ProgramError(source_loc)
<< "value of associated constant " << *value << " is not known";
}
return Convert(value, destination_type, source_loc);
}
}
explorer/interpreter/type_checker.cpp
+38 -119
View File
@@ -32,68 +32,6 @@ using llvm::isa;
namespace Carbon {
struct TypeChecker::SingleStepEqualityContext : public EqualityContext {
public:
SingleStepEqualityContext(Nonnull<const TypeChecker*> type_checker,
Nonnull<const ImplScope*> impl_scope)
: type_checker_(type_checker), impl_scope_(impl_scope) {}
// Visits the values that are equal to the given value and a single step away
// according to an equality constraint that is either scope or within a final
// impl corresponding to an associated constant. Stops and returns `false` if
// the visitor returns `false`, otherwise returns `true`.
auto VisitEqualValues(Nonnull<const Value*> value,
llvm::function_ref<bool(Nonnull<const Value*>)> visitor)
const -> bool override {
if (type_checker_->trace_stream_) {
**type_checker_->trace_stream_ << "looking for values equal to " << *value
<< " in\n"
<< *impl_scope_;
}
if (!impl_scope_->VisitEqualValues(value, visitor)) {
return false;
}
// Also look up and visit the corresponding impl if this is an associated
// constant.
if (auto* assoc = dyn_cast<AssociatedConstant>(value)) {
// Perform an impl lookup to see if we can resolve this constant.
// The source location doesn't matter, we're discarding the diagnostics.
if (auto* impl_witness = dyn_cast<ImplWitness>(&assoc->witness())) {
// Instantiate the impl to find the concrete constraint it implements.
Nonnull<const ConstraintType*> constraint =
impl_witness->declaration().constraint_type();
constraint = cast<ConstraintType>(
type_checker_->Substitute(impl_witness->bindings(), constraint));
if (type_checker_->trace_stream_) {
**type_checker_->trace_stream_ << "found constraint " << *constraint
<< " for associated constant "
<< *assoc << "\n";
}
// Look for the value of this constant within that constraint.
if (!constraint->VisitEqualValues(value, visitor)) {
return false;
}
} else {
if (type_checker_->trace_stream_) {
**type_checker_->trace_stream_
<< "Could not resolve associated constant " << *assoc << ": "
<< "witness " << assoc->witness()
<< " depends on a generic parameter\n";
}
}
}
return true;
}
private:
Nonnull<const TypeChecker*> type_checker_;
Nonnull<const ImplScope*> impl_scope_;
};
static void SetValue(Nonnull<Pattern*> pattern, Nonnull<const Value*> value) {
// TODO: find some way to CHECK that `value` is identical to pattern->value(),
// if it's already set. Unclear if `ValueEqual` is suitable, because it
@@ -107,8 +45,7 @@ static void SetValue(Nonnull<Pattern*> pattern, Nonnull<const Value*> value) {
auto TypeChecker::IsSameType(Nonnull<const Value*> type1,
Nonnull<const Value*> type2,
const ImplScope& impl_scope) const -> bool {
SingleStepEqualityContext equality_ctx(this, &impl_scope);
return TypeEqual(type1, type2, &equality_ctx);
return TypeEqual(type1, type2, std::nullopt);
}
auto TypeChecker::ExpectExactType(SourceLocation source_loc,
@@ -1223,8 +1160,8 @@ class TypeChecker::ConstraintTypeBuilder {
<< "multiple different rewrites for `.("
<< *rewrite.interface << "." << *GetName(*rewrite.constant)
<< ")`:\n"
<< " " << *existing.replacement << "\n"
<< " " << *rewrite.replacement;
<< " " << existing.replacement->value() << "\n"
<< " " << rewrite.replacement->value();
}
}
rewrite_constraints_.push_back(std::move(rewrite));
@@ -1340,6 +1277,7 @@ class TypeChecker::ConstraintTypeBuilder {
}
impl_scope->Add(impl_constraints, llvm::None, llvm::None, GetSelfWitness(),
type_checker);
// TODO: Bring equality constraints into scope too.
}
// Converts the builder into a ConstraintType. Note that this consumes the
@@ -3156,9 +3094,11 @@ auto TypeChecker::TypeCheckExp(Nonnull<Expression*> e,
ImplScope inner_impl_scope;
inner_impl_scope.AddParent(&impl_scope);
auto& self = where.self_binding();
ConstraintTypeBuilder builder(arena_, &self);
// Note, we don't want to call `TypeCheckPattern` here. Most of the setup
// for the self binding is instead done by the `ConstraintTypeBuilder`.
auto& self = where.self_binding();
CARBON_ASSIGN_OR_RETURN(Nonnull<const Value*> base_type,
TypeCheckTypeExp(&self.type(), impl_scope));
self.set_static_type(base_type);
@@ -3170,7 +3110,6 @@ auto TypeChecker::TypeCheckExp(Nonnull<Expression*> e,
base_type));
// Start with the given constraint.
ConstraintTypeBuilder builder(arena_, &self);
CARBON_RETURN_IF_ERROR(
builder.AddAndSubstitute(*this, base, builder.GetSelfType(),
builder.GetSelfWitness(), Bindings(),
@@ -3264,6 +3203,16 @@ auto TypeChecker::TypeCheckExp(Nonnull<Expression*> e,
rewrite_clause.source_loc(), {.interface = result.interface,
.constant = constant,
.replacement = replacement}));
// Also find (or add) `.Self is I`, and add `.Self.T == V`.
int index = builder.AddImplConstraint(
{.type = builder.GetSelfType(), .interface = result.interface});
auto* witness =
MakeConstraintWitnessAccess(builder.GetSelfWitness(), index);
builder.AddEqualityConstraint(
{.values = {arena_->New<AssociatedConstant>(
builder.GetSelfType(), result.interface,
constant, witness),
replacement_value}});
break;
}
}
@@ -3466,6 +3415,13 @@ auto TypeChecker::TypeCheckPattern(
}
case PatternKind::GenericBinding: {
auto& binding = cast<GenericBinding>(*p);
// The binding can be referred to in its own type via `.Self`, so set up
// its symbolic identity before we type-check and interpret the type.
auto* val = arena_->New<VariableType>(&binding);
binding.set_symbolic_identity(val);
SetValue(&binding, val);
CARBON_ASSIGN_OR_RETURN(Nonnull<const Value*> type,
TypeCheckTypeExp(&binding.type(), impl_scope));
if (expected) {
@@ -3479,10 +3435,6 @@ auto TypeChecker::TypeCheckPattern(
<< "`.Self` used in type of non-type binding `" << binding.name()
<< "`";
}
CARBON_ASSIGN_OR_RETURN(Nonnull<const Value*> val,
InterpPattern(&binding, arena_, trace_stream_));
binding.set_symbolic_identity(val);
SetValue(&binding, val);
// Create an impl binding if we have a constraint.
if (isa<ConstraintType, InterfaceType>(type)) {
@@ -4477,50 +4429,11 @@ auto TypeChecker::CheckImplIsComplete(Nonnull<const InterfaceType*> iface_type,
const auto& iface_decl = iface_type->declaration();
for (Nonnull<Declaration*> m : iface_decl.members()) {
if (auto* assoc = dyn_cast<AssociatedConstantDeclaration>(m)) {
// An associated constant must be given exactly one value.
if (LookupRewrite(impl_decl->constraint_type(), iface_type, assoc)) {
// OK, named by `=` constraint.
continue;
}
// TODO: Remove the rest of this and just reject if there's no `=`.
Nonnull<const Value*> expected = arena_->New<AssociatedConstant>(
self_type, iface_type, assoc, self_witness);
bool found_any = false;
std::optional<Nonnull<const Value*>> found_value;
std::optional<Nonnull<const Value*>> second_value;
auto visitor = [&](Nonnull<const Value*> equal_value) {
found_any = true;
if (!isa<AssociatedConstant>(equal_value)) {
if (!found_value ||
ValueEqual(equal_value, *found_value, std::nullopt)) {
found_value = equal_value;
} else {
second_value = equal_value;
return false;
}
}
return true;
};
impl_decl->constraint_type()->VisitEqualValues(expected, visitor);
if (!found_any) {
return ProgramError(impl_decl->source_loc())
<< "implementation missing " << *expected << "; have "
<< *impl_decl->constraint_type();
} else if (!found_value) {
// TODO: It's not clear what the right rule is here. Clearly
// impl T as HasX & HasY where .X == .Y {}
// ... is insufficient to establish a value for either X or Y.
// But perhaps we can allow
// impl forall [T:! HasX] T as HasY where .Y == .X {}
// An associated constant must be given a value.
if (!LookupRewrite(impl_decl->constraint_type(), iface_type, assoc)) {
return ProgramError(impl_decl->source_loc())
<< "implementation doesn't provide a concrete value for "
<< *expected;
} else if (second_value) {
return ProgramError(impl_decl->source_loc())
<< "implementation provides multiple values for " << *expected
<< ": " << **found_value << " and " << **second_value;
<< *iface_type << "." << assoc->binding().name();
}
} else if (isa<InterfaceImplDeclaration, InterfaceExtendsDeclaration>(m)) {
// These get translated into constraints so there's nothing we need to
@@ -4685,22 +4598,28 @@ auto TypeChecker::DeclareImplDeclaration(Nonnull<ImplDeclaration*> impl_decl,
self_impl_scope.Add(iface_type, impl_type_value, self_witness, *this);
}
}
// This impl also provides all of its equalities.
// TODO: Only the ones from rewrite constraints.
for (auto& eq : constraint_type->equality_constraints()) {
self_impl_scope.AddEqualityConstraint(&eq);
}
// Ensure that's enough for our interface to be satisfied.
CARBON_ASSIGN_OR_RETURN(
impl_witness, self_impl_scope.Resolve(constraint_type, impl_type_value,
impl_decl->source_loc(), *this));
}
// Declare the impl members.
ScopeInfo impl_scope_info = ScopeInfo::ForNonClassScope(&impl_scope);
// Declare the impl members. An `impl` behaves like a class scope.
ScopeInfo impl_scope_info =
ScopeInfo::ForClassScope(scope_info, &impl_scope, generic_bindings);
for (Nonnull<Declaration*> m : impl_decl->members()) {
CARBON_RETURN_IF_ERROR(DeclareDeclaration(m, impl_scope_info));
}
// Create the implied impl bindings.
CARBON_RETURN_IF_ERROR(CheckAndAddImplBindings(impl_decl, impl_type_value,
self_witness, impl_witness,
generic_bindings, scope_info));
CARBON_RETURN_IF_ERROR(
CheckAndAddImplBindings(impl_decl, impl_type_value, self_witness,
impl_witness, generic_bindings, impl_scope_info));
if (trace_stream_) {
**trace_stream_ << "** finished declaring impl " << *impl_decl->impl_type()
explorer/interpreter/type_checker.h
-1
View File
@@ -80,7 +80,6 @@ class TypeChecker {
-> Nonnull<const Witness*>;
private:
struct SingleStepEqualityContext;
class ConstraintTypeBuilder;
class SubstitutedGenericBindings;
class ArgumentDeduction;
explorer/interpreter/value.cpp
+7 -4
View File
@@ -512,7 +512,10 @@ void Value::Print(llvm::raw_ostream& out) const {
break;
case Value::Kind::AssociatedConstant: {
const auto& assoc = cast<AssociatedConstant>(*this);
out << "(" << assoc.base() << ")." << assoc.constant().binding().name();
out << "(" << assoc.base() << ").(";
PrintNameWithBindings(out, &assoc.interface().declaration(),
assoc.interface().args());
out << "." << assoc.constant().binding().name() << ")";
break;
}
case Value::Kind::ContinuationValue: {
@@ -629,7 +632,7 @@ auto TypeEqual(Nonnull<const Value*> t1, Nonnull<const Value*> t2,
return true;
}
if (t1->kind() != t2->kind()) {
if (isa<AssociatedConstant>(t1) || isa<AssociatedConstant>(t2)) {
if (IsValueKindDependent(t1) || IsValueKindDependent(t2)) {
return ValueEqual(t1, t2, equality_ctx);
}
return false;
@@ -942,7 +945,7 @@ auto ValueEqual(Nonnull<const Value*> v1, Nonnull<const Value*> v2,
// associated constant; otherwise we should be able to do better by looking
// at the structures of the values.
if (equality_ctx) {
if (isa<AssociatedConstant>(v1)) {
if (IsValueKindDependent(v1)) {
auto visitor = [&](Nonnull<const Value*> maybe_v2) {
return !ValueStructurallyEqual(v2, maybe_v2, equality_ctx);
};
@@ -950,7 +953,7 @@ auto ValueEqual(Nonnull<const Value*> v1, Nonnull<const Value*> v2,
return true;
}
}
if (isa<AssociatedConstant>(v2)) {
if (IsValueKindDependent(v2)) {
auto visitor = [&](Nonnull<const Value*> maybe_v1) {
return !ValueStructurallyEqual(v1, maybe_v1, equality_ctx);
};
explorer/interpreter/value.h
+7
View File
@@ -121,6 +121,13 @@ class Value {
const Kind kind_;
};
// Returns whether the fully-resolved kind that this value will eventually have
// is currently unknown, because it depends on a generic parameter.
inline bool IsValueKindDependent(Nonnull<const Value*> type) {
return type->kind() == Value::Kind::VariableType ||
type->kind() == Value::Kind::AssociatedConstant;
}
// Base class for types holding contextual information by which we can
// determine whether values are equal.
class EqualityContext {
explorer/testdata/assoc_const/fail_different_type.carbon
Vendored
+27
View File
@@ -0,0 +1,27 @@
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// RUN: %{not} %{explorer} %s | %{FileCheck-strict} %s
// RUN: %{not} %{explorer-trace} %s | %{FileCheck-allow-unmatched} %s
// AUTOUPDATE: %{explorer} %s
package ExplorerTest api;
interface Iface {
let T:! Type;
}
fn F(T:! Iface where .T == i32) {}
class Good {}
class Bad {}
external impl Good as Iface where .T = i32 {}
external impl Bad as Iface where .T = Bad {}
fn Main() -> i32 {
F(Good);
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_different_type.carbon:[[@LINE+1]]: constraint requires that class Bad == i32, which is not known to be true
F(Bad);
return 0;
}
explorer/testdata/assoc_const/fail_different_value.carbon
Vendored
+27
View File
@@ -0,0 +1,27 @@
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// RUN: %{not} %{explorer} %s | %{FileCheck-strict} %s
// RUN: %{not} %{explorer-trace} %s | %{FileCheck-allow-unmatched} %s
// AUTOUPDATE: %{explorer} %s
package ExplorerTest api;
interface Iface {
let N:! i32;
}
fn F(T:! Iface where .N == 5) {}
class Good {}
class Bad {}
external impl Good as Iface where .N = 5 {}
external impl Bad as Iface where .N = 4 {}
fn Main() -> i32 {
F(Good);
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_different_value.carbon:[[@LINE+1]]: constraint requires that 4 == 5, which is not known to be true
F(Bad);
return 0;
}
explorer/testdata/assoc_const/fail_equal_indirectly.carbon
Vendored
+38
View File
@@ -0,0 +1,38 @@
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// RUN: %{not} %{explorer} %s | %{FileCheck-strict} %s
// RUN: %{not} %{explorer-trace} %s | %{FileCheck-allow-unmatched} %s
// AUTOUPDATE: %{explorer} %s
package ExplorerTest api;
interface Iface {
let T:! Type;
}
fn F[T:! Iface where .T == i32](x: T) {}
class Class {
impl as Iface where .T = i32 {}
}
// OK, constraint on `F` rewritten to `T:! Iface where U == i32`, which we can
// prove from the constraint on `U`.
fn G[U:! Type where .Self == i32, T:! Iface where .T = U](x: T, y: U) {
F(x);
}
// Not OK: would require looking through two levels of `==`.
fn H[U:! Type where .Self == i32, T:! Iface where .T == U](x: T, y: U) {
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_equal_indirectly.carbon:[[@LINE+1]]: constraint requires that (T).(Iface.T) == i32, which is not known to be true
F(x);
}
fn Main() -> i32 {
var x: Class = {};
G(x, 0);
H(x, 0);
return 0;
}
explorer/testdata/assoc_const/fail_equal_to_dependent_type.carbon
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+35
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@@ -0,0 +1,35 @@
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// RUN: %{not} %{explorer} %s | %{FileCheck-strict} %s
// RUN: %{not} %{explorer-trace} %s | %{FileCheck-allow-unmatched} %s
// AUTOUPDATE: %{explorer} %s
package ExplorerTest api;
interface Iface {
let T:! Type;
}
fn F[T:! Iface where .T == i32](x: T) {}
fn G[T:! Iface where .T == i32](x: T) {
F(x);
}
fn H[T:! Iface](x: T) {
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_equal_to_dependent_type.carbon:[[@LINE+1]]: constraint requires that (T).(Iface.T) == i32, which is not known to be true
F(x);
}
class Class {
impl as Iface where .T = i32 {}
}
fn Main() -> i32 {
var x: Class = {};
G(x);
H(x);
return 0;
}
explorer/testdata/assoc_const/fail_incomplete_impl_1.carbon
Vendored
+2 -2
View File
@@ -14,7 +14,7 @@ interface HasThreeTypes {
let C:! Type;
}
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_incomplete_impl_1.carbon:[[@LINE+1]]: implementation missing (i32).B; have constraint interface HasThreeTypes where i32 is interface HasThreeTypes and (i32).A == i32 and (i32).C == i32
external impl i32 as HasThreeTypes where .A == i32 and .C == i32 {}
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_incomplete_impl_1.carbon:[[@LINE+1]]: implementation doesn't provide a concrete value for interface HasThreeTypes.B
external impl i32 as HasThreeTypes where .A = i32 and .C = i32 {}
fn Main() -> i32 { return 0; }
explorer/testdata/assoc_const/fail_incomplete_impl_2.carbon
Vendored
+2 -2
View File
@@ -14,7 +14,7 @@ interface HasThreeTypes {
let C:! Type;
}
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_incomplete_impl_2.carbon:[[@LINE+1]]: implementation doesn't provide a concrete value for (i32).B
external impl i32 as HasThreeTypes where .A == i32 and .B == .C {}
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_incomplete_impl_2.carbon:[[@LINE+1]]: implementation doesn't provide a concrete value for interface HasThreeTypes.C
external impl i32 as HasThreeTypes where .A = i32 and .B = .C {}
fn Main() -> i32 { return 0; }
explorer/testdata/assoc_const/fail_indirectly_equal.carbon
Vendored
+1 -1
View File
@@ -23,7 +23,7 @@ fn F2[U:! A where .T == i32](x: i32) -> U.T {
}
fn F3[T:! A where .T == i32, U:! A where .T == i32](x: T.T) -> U.T {
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_indirectly_equal.carbon:[[@LINE+1]]: type error in return value: '(T).T' is not implicitly convertible to '(U).T'
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_indirectly_equal.carbon:[[@LINE+1]]: type error in return value: '(T).(A.T)' is not implicitly convertible to '(U).(A.T)'
return x;
}
explorer/testdata/assoc_const/fail_match_in_deduction.carbon
Vendored
+2 -2
View File
@@ -13,7 +13,7 @@ package ExplorerTest api;
interface Vector {
let Dim:! i32;
}
external impl (i32, i32, i32) as Vector where .Dim == 3 {}
external impl (i32, i32, i32) as Vector where .Dim = 3 {}
class Point(Scalar:! Type, Dim:! i32) {}
@@ -22,7 +22,7 @@ fn F[Scalar:! Type, V:! Vector where .Dim == 3](p: Point(Scalar, V.Dim), v: V) {
fn G[Scalar:! Type](p: Point(Scalar, 3)) {}
fn H[V:! Vector where .Dim == 3](v: V) {
var p: Point(i32, V.Dim) = {};
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_match_in_deduction.carbon:[[@LINE+1]]: mismatch in non-type values, `(V).Dim` != `3`
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_match_in_deduction.carbon:[[@LINE+1]]: mismatch in non-type values, `(V).(Vector.Dim)` != `3`
G(p);
}
explorer/testdata/assoc_const/fail_multi_impl_scoping.carbon
Vendored
+3 -4
View File
@@ -18,7 +18,7 @@ interface B {
}
class C(T:! Type) {
impl as A & B where .TA == i32 and .TB == i32 {
impl as A & B where .TA = i32 and .TB = i32 {
fn FA() -> i32 {
// OK, know that TA is i32 here.
let v: Self.(A.TA) = 1;
@@ -29,10 +29,8 @@ class C(T:! Type) {
// OK, know that TB is i32 here.
let v: Self.(B.TB) = 2;
// Don't know that TA is i32; it could be specialized.
// TODO: We should not accept this.
let w: Self.(A.TA) = 3;
// TODO: This error is confusing. We should be diagnosing the previous
// line because we don't know that `3` can be converted to `Self.(A.TA)`.
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_multi_impl_scoping.carbon:[[@LINE+1]]: type error in return value: '((class C(T = T)).TB).Result' is not implicitly convertible to 'i32'
return v + w;
}
}
@@ -40,6 +38,7 @@ class C(T:! Type) {
external impl C(i32) as B where .TB == () {
fn FB() -> () { return (); }
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_multi_impl_scoping.carbon:[[@LINE+1]]: ambiguous implementations of interface B for class C(T = i32)
}
fn Main() -> i32 { return C(i32).FB(); }
explorer/testdata/assoc_const/fail_multiple_deduction.carbon
Vendored
+2 -2
View File
@@ -17,8 +17,8 @@ interface HasThreeTypes {
fn F[T:! Type](x: (T, T, T));
fn G[X:! HasThreeTypes where .A == .B and .B == .C and .C == .A](x: X) {
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_multiple_deduction.carbon:[[@LINE+3]]: deduced multiple different values for T:! Type:
// CHECK:STDERR: (X).A
// CHECK:STDERR: (X).B
// CHECK:STDERR: (X).(HasThreeTypes.A)
// CHECK:STDERR: (X).(HasThreeTypes.B)
F(x.Make());
}
explorer/testdata/assoc_const/fail_overspecified_impl.carbon
Vendored
+4 -2
View File
@@ -12,7 +12,9 @@ interface HasType {
let T:! Type;
}
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_overspecified_impl.carbon:[[@LINE+1]]: implementation provides multiple values for (i32).T: i32 and {.a: i32}
external impl i32 as HasType where .T == i32 and .T == {.a: i32} {}
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_overspecified_impl.carbon:[[@LINE+3]]: multiple different rewrites for `.(interface HasType.T)`:
// CHECK:STDERR: i32
// CHECK:STDERR: {.a: i32}
external impl i32 as HasType where .T = i32 and .T = {.a: i32} {}
fn Main() -> i32 { return 0; }
explorer/testdata/assoc_const/fail_unknown_value.carbon
Vendored
+2 -2
View File
@@ -13,12 +13,12 @@ interface Iface { let N:! i32; }
fn PickType(N: i32) -> Type { return i32; }
fn F[T:! Iface](x: T) -> i32 {
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_unknown_value.carbon:[[@LINE+1]]: value of associated constant (T).N is not known
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_unknown_value.carbon:[[@LINE+1]]: value of associated constant (T).(Iface.N) is not known
var x: PickType(T.N) = 0;
return x;
}
impl i32 as Iface where .N == 5 {}
impl i32 as Iface where .N = 5 {}
fn Main() -> i32 {
return F(0);
explorer/testdata/assoc_const/fail_unknown_value_specified_in_constraint.carbon
Vendored
+1 -1
View File
@@ -14,7 +14,7 @@ fn PickType(N: i32) -> Type { return i32; }
fn F[T:! Iface where .N == 5](x: T) -> i32 {
// TODO: This should be valid: the value of T.N is known to be 5 here.
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_unknown_value_specified_in_constraint.carbon:[[@LINE+1]]: value of associated constant (T).N is not known
// CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assoc_const/fail_unknown_value_specified_in_constraint.carbon:[[@LINE+1]]: value of associated constant (T).(Iface.N) is not known
var x: PickType(T.N) = 0;
return x;
}
explorer/testdata/assoc_const/impl_lookup.carbon
Vendored
+1 -1
View File
@@ -26,7 +26,7 @@ class AlmostI32 {
}
}
impl i32 as Frob where .Result == AlmostI32 {
impl i32 as Frob where .Result = AlmostI32 {
fn F[me: Self]() -> AlmostI32 { return {.val = me}; }
}
explorer/testdata/assoc_const/implement.carbon
Vendored
+1 -1
View File
@@ -16,7 +16,7 @@ interface Vector {
class Point {
var x: i32;
var y: i32;
impl as Vector where .Dim == 2 {}
impl as Vector where .Dim = 2 {}
}
fn Main() -> i32 {
explorer/testdata/assoc_const/member_of_value.carbon
Vendored
+1 -1
View File
@@ -16,7 +16,7 @@ interface Vector {
class Point {
var x: i32;
var y: i32;
impl as Vector where .Dim == 2 {}
impl as Vector where .Dim = 2 {}
}
fn Main() -> i32 {
explorer/testdata/assoc_const/pass_equal_to_rewrite.carbon
Vendored
+34
View File
@@ -0,0 +1,34 @@
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// RUN: %{explorer} %s | %{FileCheck-strict} %s
// RUN: %{explorer-trace} %s | %{FileCheck-allow-unmatched} %s
// AUTOUPDATE: %{explorer} %s
// CHECK:STDOUT: result: 1
package ExplorerTest api;
interface Container {
let Element:! Type;
fn Front[me: Self]() -> Element;
}
fn A[T:! Container where .Element = i32](x: T) -> T.Element {
return x.Front();
}
fn B[T:! Container where .Element == i32](x: T) -> T.Element {
return A(x);
}
external impl (i32, i32) as Container where .Element = i32 {
fn Front[me: Self]() -> i32 {
let (a: i32, b: i32) = me;
return a;
}
}
fn Main() -> i32 {
return B((1, 2));
}
explorer/testdata/assoc_const/pass_rewrite_to_equal.carbon
Vendored
+34
View File
@@ -0,0 +1,34 @@
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// RUN: %{explorer} %s | %{FileCheck-strict} %s
// RUN: %{explorer-trace} %s | %{FileCheck-allow-unmatched} %s
// AUTOUPDATE: %{explorer} %s
// CHECK:STDOUT: result: 1
package ExplorerTest api;
interface Container {
let Element:! Type;
fn Front[me: Self]() -> Element;
}
fn A[T:! Container where .Element == i32](x: T) -> T.Element {
return x.Front();
}
fn B[T:! Container where .Element = i32](x: T) -> T.Element {
return A(x);
}
external impl (i32, i32) as Container where .Element = i32 {
fn Front[me: Self]() -> i32 {
let (a: i32, b: i32) = me;
return a;
}
}
fn Main() -> i32 {
return B((1, 2));
}
explorer/testdata/assoc_const/simple_constraint.carbon
Vendored
+2 -2
View File
@@ -14,12 +14,12 @@ interface Frob {
fn F[me: Self]() -> Result;
}
fn Use[T:! Frob where .Result == .Self](x: T) -> T {
fn Use[T:! Frob where .Result = .Self](x: T) -> T {
var v: T = x.F();
return v;
}
impl i32 as Frob where .Result == i32 {
impl i32 as Frob where .Result = i32 {
fn F[me: Self]() -> i32 { return me + 1; }
}
explorer/testdata/assoc_const/simple_equality.carbon
Vendored
+1 -1
View File
@@ -19,7 +19,7 @@ fn Use[T:! Frob](x: T) -> T.Result {
return v;
}
impl i32 as Frob where .Result == i32 {
impl i32 as Frob where .Result = i32 {
fn F[me: Self]() -> i32 { return 0; }
}
explorer/testdata/constraint/binding_dot_self_in_constraint.carbon
Vendored
+24
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@@ -0,0 +1,24 @@
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// RUN: %{explorer} %s | %{FileCheck-strict} %s
// RUN: %{explorer-trace} %s | %{FileCheck-allow-unmatched} %s
// AUTOUPDATE: %{explorer} %s
// CHECK:STDOUT: result: 6
package ExplorerTest api;
// The constraint here resolves to:
//
// MulWith(T) where <ConstraintSelf>.(MulWith(T).Result) == <ConstraintSelf>
//
// Note in particular that this involves a member of `MulWith(T)`, so we need
// `T` to have a symbolic identity when checking its own type.
fn DoMul[T:! MulWith(.Self) where .Result == .Self](x: T, y: T) -> T {
return x * y;
}
fn Main() -> i32 {
return DoMul(2, 3);
}
explorer/testdata/operators/add.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as AddWith(i32) where .Result == A {
external impl A as AddWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n + rhs}; }
}
explorer/testdata/operators/bit_and.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as BitAndWith(i32) where .Result == A {
external impl A as BitAndWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n & rhs}; }
}
explorer/testdata/operators/bit_complement.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as BitComplement where .Result == A {
external impl A as BitComplement where .Result = A {
fn Op[me: Self]() -> A { return {.n = ^me.n}; }
}
explorer/testdata/operators/bit_or.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as BitOrWith(i32) where .Result == A {
external impl A as BitOrWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n | rhs}; }
}
explorer/testdata/operators/bit_xor.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as BitXorWith(i32) where .Result == A {
external impl A as BitXorWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n ^ rhs}; }
}
explorer/testdata/operators/div.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as DivWith(i32) where .Result == A {
external impl A as DivWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n / rhs}; }
}
explorer/testdata/operators/left_shift.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as LeftShiftWith(i32) where .Result == A {
external impl A as LeftShiftWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n << rhs}; }
}
explorer/testdata/operators/mod.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as ModWith(i32) where .Result == A {
external impl A as ModWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n % rhs}; }
}
explorer/testdata/operators/mul.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as MulWith(i32) where .Result == A {
external impl A as MulWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n * rhs}; }
}
explorer/testdata/operators/negate.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as Negate where .Result == A {
external impl A as Negate where .Result = A {
fn Op[me: Self]() -> A { return {.n = -me.n}; }
}
explorer/testdata/operators/right_shift.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as RightShiftWith(i32) where .Result == A {
external impl A as RightShiftWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n >> rhs}; }
}
explorer/testdata/operators/sub.carbon
Vendored
+1 -1
View File
@@ -11,7 +11,7 @@ package ExplorerTest api;
class A { var n: i32; }
external impl A as SubWith(i32) where .Result == A {
external impl A as SubWith(i32) where .Result = A {
fn Op[me: Self](rhs: i32) -> A { return {.n = me.n - rhs}; }
}
explorer/testdata/print/associated_constant.carbon
Vendored
+2 -2
View File
@@ -15,8 +15,8 @@ interface HasName {
let Name:! String;
}
external impl i32 as HasName where .Name == "i32" {}
external impl String as HasName where .Name == "String" {}
external impl i32 as HasName where .Name = "i32" {}
external impl String as HasName where .Name = "String" {}
fn Main() -> i32 {
Print(i32.(HasName.Name));