Files
carbon-lang/toolchain/check/handle_alias.cpp
T
Richard Smith ae6846197a Remove trailing () from Core.*Literal and Core.Bool. (#7313)
We exposed `Core.IntLiteral()`, `Core.FloatLiteral()`,
`Core.CharLiteral()`, and `Core.Bool()` as functions as a workaround,
because we had no way to provide the type names without parentheses that
the design requests. But now we can do so, by using an alias. Switch all
of these over from being functions to simply being names of the
corresponding types.

Assisted-by: Gemini via Antigravity
2026-06-05 22:33:30 +00:00

91 lines
3.4 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/convert.h"
#include "toolchain/check/generic.h"
#include "toolchain/check/handle.h"
#include "toolchain/check/inst.h"
#include "toolchain/check/modifiers.h"
#include "toolchain/check/name_component.h"
#include "toolchain/parse/node_ids.h"
#include "toolchain/sem_ir/expr_info.h"
#include "toolchain/sem_ir/ids.h"
#include "toolchain/sem_ir/typed_insts.h"
namespace Carbon::Check {
auto HandleParseNode(Context& context, Parse::AliasIntroducerId /*node_id*/)
-> bool {
// Aliases can't be generic, but we might have parsed a generic parameter in
// their name, so enter a generic scope just in case.
StartGenericDecl(context);
// Optional modifiers and the name follow.
context.decl_introducer_state_stack().Push<Lex::TokenKind::Alias>();
context.decl_name_stack().PushScopeAndStartName();
return true;
}
auto HandleParseNode(Context& /*context*/,
Parse::AliasInitializerId /*node_id*/) -> bool {
return true;
}
auto HandleParseNode(Context& context, Parse::AliasId /*node_id*/) -> bool {
auto [expr_node, expr_id] = context.node_stack().PopExprWithNodeId();
auto name_context = context.decl_name_stack().FinishName(
PopNameComponentWithoutParams(context, Lex::TokenKind::Alias));
DiscardGenericDecl(context);
auto introducer =
context.decl_introducer_state_stack().Pop<Lex::TokenKind::Alias>();
LimitModifiersOnDecl(context, introducer, KeywordModifierSet::Access);
auto entity_name_id = context.entity_names().Add(
{.name_id = name_context.name_id_for_new_inst(),
.parent_scope_id = name_context.parent_scope_id});
switch (SemIR::GetExprCategory(context.sem_ir(), expr_id)) {
case SemIR::ExprCategory::Value:
case SemIR::ExprCategory::EphemeralRef:
case SemIR::ExprCategory::DurableRef:
case SemIR::ExprCategory::NotExpr:
case SemIR::ExprCategory::Error:
// An alias can refer to a value, a reference, or a non-expression name
// such as a function or namespace.
break;
case SemIR::ExprCategory::ReprInitializing:
case SemIR::ExprCategory::InPlaceInitializing:
case SemIR::ExprCategory::Mixed:
case SemIR::ExprCategory::Dependent:
case SemIR::ExprCategory::RefTagged:
case SemIR::ExprCategory::Pattern:
// For any other kind of expression, convert to a value or reference.
// TODO: Should we allow or require `ref` tagging for reference aliases?
expr_id = ConvertToValueOrRefExpr(context, expr_id);
break;
}
if (!context.constant_values().Get(expr_id).is_constant()) {
CARBON_DIAGNOSTIC(AliasRequiresConstantValue, Error,
"alias refers to a runtime value");
context.emitter().Emit(expr_node, AliasRequiresConstantValue);
}
auto alias_id = AddInst<SemIR::AliasBinding>(
context, name_context.loc_id,
{.type_id = context.insts().Get(expr_id).type_id(),
.entity_name_id = entity_name_id,
.value_id = expr_id});
// Add the name of the binding to the current scope.
context.decl_name_stack().PopScope();
context.decl_name_stack().AddNameOrDiagnose(
name_context, alias_id, introducer.modifier_set.GetAccessKind());
return true;
}
} // namespace Carbon::Check