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https://github.com/carbon-language/carbon-lang.git
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Burak EmirandDana Jansens
fec6ce2f9f
This implements proposal #2022, with changes from #3763 and leads answers on #6448 Detection of unusedness is happening in ~~`toolchain/check/dataflow_analysis.cpp`~~ next PR. See [here](https://github.com/burakemir/carbon-lang/tree/unused_pattern_bindings_p2022_impl_part2) for preview. ~~All test cases with unused bindings were updated in order to avoid polluting test output.~~ --------- Co-authored-by: Dana Jansens <danakj@orodu.net>
37 lines
1.2 KiB
C++
37 lines
1.2 KiB
C++
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
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// Exceptions. See /LICENSE for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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#include "toolchain/parse/context.h"
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#include "toolchain/parse/handle.h"
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namespace Carbon::Parse {
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auto HandleUnusedPattern(Context& context) -> void {
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auto state = context.PopState();
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if (state.in_unused_pattern) {
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CARBON_DIAGNOSTIC(NestedUnused, Error,
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"`unused` nested within another `unused`");
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context.emitter().Emit(*context.position(), NestedUnused);
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state.has_error = true;
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}
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context.PushState(StateKind::FinishUnusedPattern);
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context.ConsumeChecked(Lex::TokenKind::Unused);
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context.PushStateForPattern(StateKind::Pattern, state.in_var_pattern,
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/*in_unused_pattern=*/true);
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}
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auto HandleFinishUnusedPattern(Context& context) -> void {
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auto state = context.PopState();
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context.AddNode(NodeKind::UnusedPattern, state.token, state.has_error);
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// Propagate errors to the parent state so that they can take different
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// actions on invalid patterns.
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if (state.has_error) {
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context.ReturnErrorOnState();
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}
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}
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} // namespace Carbon::Parse
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