Files
carbon-lang/toolchain/check/handle_namespace.cpp
T

57 lines
2.3 KiB
C++

// 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
#include "toolchain/check/context.h"
#include "toolchain/check/decl_state.h"
#include "toolchain/check/modifiers.h"
#include "toolchain/sem_ir/ids.h"
namespace Carbon::Check {
auto HandleNamespaceStart(Context& context, Parse::NamespaceStartId /*node_id*/)
-> bool {
// Optional modifiers and the name follow.
context.decl_state_stack().Push(DeclState::Namespace);
context.decl_name_stack().PushScopeAndStartName();
return true;
}
auto HandleNamespace(Context& context, Parse::NamespaceId node_id) -> bool {
auto name_context = context.decl_name_stack().FinishName();
LimitModifiersOnDecl(context, KeywordModifierSet::None,
Lex::TokenKind::Namespace);
auto namespace_inst = SemIR::Namespace{
context.GetBuiltinType(SemIR::BuiltinKind::NamespaceType),
SemIR::NameScopeId::Invalid, SemIR::InstId::Invalid};
auto namespace_id = context.AddPlaceholderInst({node_id, namespace_inst});
namespace_inst.name_scope_id = context.name_scopes().Add(
namespace_id, name_context.name_id_for_new_inst(),
name_context.enclosing_scope_id_for_new_inst());
context.ReplaceInstBeforeConstantUse(namespace_id, namespace_inst);
auto existing_inst_id =
context.decl_name_stack().LookupOrAddName(name_context, namespace_id);
if (existing_inst_id.is_valid()) {
// If there's a name conflict with a namespace, "merge" by using the
// previous declaration. Otherwise, diagnose the issue.
if (auto existing =
context.insts().TryGetAs<SemIR::Namespace>(existing_inst_id)) {
// When the name conflict is an imported namespace, fill the location ID
// so that future diagnostics point at this declaration.
if (existing->import_id.is_valid() &&
!context.insts().GetLocId(existing_inst_id).is_valid()) {
context.SetNamespaceNodeId(existing_inst_id, node_id);
}
} else {
context.DiagnoseDuplicateName(namespace_id, existing_inst_id);
}
}
context.decl_name_stack().PopScope();
context.decl_state_stack().Pop(DeclState::Namespace);
return true;
}
} // namespace Carbon::Check