mirror of
https://github.com/carbon-language/carbon-lang.git
synced 2026-09-24 21:20:11 +01:00
78 lines
2.6 KiB
C++
78 lines
2.6 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/parse/context.h"
|
|
#include "toolchain/parse/handle.h"
|
|
|
|
namespace Carbon::Parse {
|
|
|
|
static auto ExpectAsOrTypeExpression(Context& context) -> void {
|
|
if (context.PositionIs(Lex::TokenKind::As)) {
|
|
// as <expression> ...
|
|
context.AddLeafNode(NodeKind::ImplDefaultSelfAs, context.Consume());
|
|
context.PushState(StateKind::Expr);
|
|
} else {
|
|
// <expression> as <expression>...
|
|
context.PushState(StateKind::ImplBeforeAs);
|
|
context.PushStateForExpr(PrecedenceGroup::ForImplAs());
|
|
}
|
|
}
|
|
|
|
auto HandleImplAfterIntroducer(Context& context) -> void {
|
|
auto state = context.PopState();
|
|
state.kind = StateKind::DeclOrDefinitionAsImpl;
|
|
context.PushState(state);
|
|
|
|
if (context.PositionIs(Lex::TokenKind::Forall)) {
|
|
// forall [<implicit parameter list>] ...
|
|
context.PushState(StateKind::ImplAfterForall);
|
|
context.AddLeafNode(NodeKind::Forall, context.Consume());
|
|
if (context.PositionIs(Lex::TokenKind::OpenSquareBracket)) {
|
|
context.PushState(StateKind::PatternListAsImplicit);
|
|
} else {
|
|
CARBON_DIAGNOSTIC(ImplExpectedAfterForall, Error,
|
|
"expected `[` after `forall` in `impl` declaration");
|
|
context.emitter().Emit(*context.position(), ImplExpectedAfterForall);
|
|
context.ReturnErrorOnState();
|
|
// If we aren't producing a node from the PatternListAsImplicit state,
|
|
// we still need to create a node to be the child of the `ImplForall`
|
|
// token created in the `ImplAfterForall` state.
|
|
context.AddInvalidParse(*context.position());
|
|
}
|
|
} else {
|
|
// One of:
|
|
// as <expression> ...
|
|
// <expression> as <expression>...
|
|
ExpectAsOrTypeExpression(context);
|
|
}
|
|
}
|
|
|
|
auto HandleImplAfterForall(Context& context) -> void {
|
|
auto state = context.PopState();
|
|
if (state.has_error) {
|
|
context.ReturnErrorOnState();
|
|
}
|
|
// One of:
|
|
// as <expression> ...
|
|
// <expression> as <expression>...
|
|
ExpectAsOrTypeExpression(context);
|
|
}
|
|
|
|
auto HandleImplBeforeAs(Context& context) -> void {
|
|
auto state = context.PopState();
|
|
if (auto as = context.ConsumeIf(Lex::TokenKind::As)) {
|
|
context.AddNode(NodeKind::ImplTypeAs, *as, state.has_error);
|
|
context.PushState(StateKind::Expr);
|
|
} else {
|
|
if (!state.has_error) {
|
|
CARBON_DIAGNOSTIC(ImplExpectedAs, Error,
|
|
"expected `as` in `impl` declaration");
|
|
context.emitter().Emit(*context.position(), ImplExpectedAs);
|
|
}
|
|
context.ReturnErrorOnState();
|
|
}
|
|
}
|
|
|
|
} // namespace Carbon::Parse
|