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

78 lines
3.1 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/modifiers.h"
#include "toolchain/sem_ir/inst.h"
namespace Carbon::Check {
auto HandleLetIntroducer(Context& context, Parse::LetIntroducerId parse_node)
-> bool {
context.decl_state_stack().Push(DeclState::Let);
// Push a bracketing node to establish the pattern context.
context.node_stack().Push(parse_node);
return true;
}
auto HandleLetInitializer(Context& /*context*/,
Parse::LetInitializerId /*parse_node*/) -> bool {
return true;
}
auto HandleLetDecl(Context& context, Parse::LetDeclId parse_node) -> bool {
auto value_id = context.node_stack().PopExpr();
if (context.node_stack().PeekIs<Parse::NodeKind::TuplePattern>()) {
return context.TODO(parse_node, "tuple pattern in let");
}
SemIR::InstId pattern_id = context.node_stack().PopPattern();
context.node_stack()
.PopAndDiscardSoloParseNode<Parse::NodeKind::LetIntroducer>();
// Process declaration modifiers.
// TODO: For a qualified `let` declaration, this should use the target scope
// of the name introduced in the declaration. See #2590.
CheckAccessModifiersOnDecl(context, Lex::TokenKind::Let,
context.scope_stack().PeekNameScopeId());
RequireDefaultFinalOnlyInInterfaces(context, Lex::TokenKind::Let,
context.scope_stack().PeekNameScopeId());
LimitModifiersOnDecl(
context, KeywordModifierSet::Access | KeywordModifierSet::Interface,
Lex::TokenKind::Let);
auto modifiers = context.decl_state_stack().innermost().modifier_set;
if (!!(modifiers & KeywordModifierSet::Access)) {
context.TODO(context.decl_state_stack().innermost().saw_access_modifier,
"access modifier");
}
if (!!(modifiers & KeywordModifierSet::Interface)) {
context.TODO(context.decl_state_stack().innermost().saw_decl_modifier,
"interface modifier");
}
context.decl_state_stack().Pop(DeclState::Let);
// Convert the value to match the type of the pattern.
auto pattern = context.insts().GetWithParseNode(pattern_id);
value_id = ConvertToValueOfType(context, parse_node, value_id,
pattern.inst.type_id());
// Update the binding with its value and add it to the current block, after
// the computation of the value.
// TODO: Support other kinds of pattern here.
auto bind_name = pattern.inst.As<SemIR::AnyBindName>();
CARBON_CHECK(!bind_name.value_id.is_valid())
<< "Binding should not already have a value!";
bind_name.value_id = value_id;
pattern.inst = bind_name;
context.ReplaceInstBeforeConstantUse(pattern_id, pattern);
context.inst_block_stack().AddInstId(pattern_id);
// Add the name of the binding to the current scope.
auto name_id = context.bind_names().Get(bind_name.bind_name_id).name_id;
context.AddNameToLookup(name_id, pattern_id);
return true;
}
} // namespace Carbon::Check