mirror of
https://github.com/carbon-language/carbon-lang.git
synced 2026-10-05 22:02:55 +01:00
Chandler Carruth
8be274cf60
Implement the toolchain side of proposal #7254, removing the `:!` binding syntax for generic and template parameters in favor of the keywords `generic`, `template`, and `runtime` plus contextual defaults for phase. For valid programs this is semantics-preserving: each binding resolves to the same phase, and produces the same SemIR, as it did under `:!`/`:`. The parser derives a binding's phase from its syntactic context plus any explicit phase keyword; new diagnostics and error recovery for misused keywords are described below. Implementation details for each component: - Lexer: remove the `:!` (`ColonExclaim`) token, move its virtual parse-node budget onto `:`, and add the `generic` and `runtime` keywords. - Parser: thread a `BindingContext` (`ExplicitParam`, `DeducedParam`, or `CompileTimeEntityParam`) from declaration introducers down through parameter lists to each binding pattern, using a one-token lookahead to distinguish a name-qualifier parameter list from a declaration's own final list. Parameters of a compile-time entity (`class`, `interface`, `constraint`, `choice`, `alias`, `export`, `namespace`) and deduced `[]` parameters default to checked generic; explicit function parameters and local bindings default to runtime. `HandleBindingPattern` resolves the phase from that context plus the keyword: a `generic` keyword needs no node of its own (the phase is carried by the binding's node kind), while a `runtime` keyword is preserved as a `RuntimeBindingName` node so `check` can name it in a diagnostic. A phase keyword that is merely redundant with the contextual default is diagnosed here, without invalidating the parse tree. - Check: a phase keyword that is invalid for its context (for example `runtime` on a checked-generic parameter) is diagnosed here, and recovers by building an error binding that still introduces the name so that later uses of it do not produce cascading errors. The removed `:!` syntax is now rejected as an ordinary parse error. The `form`/`:?`/`->?` ("extended types") portion of proposal #7254 is left for a separate change. Assisted-by: Claude Code
180 lines
5.5 KiB
Plaintext
180 lines
5.5 KiB
Plaintext
// 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-FILE: toolchain/testing/testdata/min_prelude/convert.carbon
|
|
//
|
|
// AUTOUPDATE
|
|
// TIP: To test this file alone, run:
|
|
// TIP: bazel test //toolchain/testing:file_test --test_arg=--file_tests=toolchain/check/testdata/facet/named_constant.carbon
|
|
// TIP: To dump output, run:
|
|
// TIP: bazel run //toolchain/testing:file_test -- --dump_output --file_tests=toolchain/check/testdata/facet/named_constant.carbon
|
|
|
|
// --- fail_todo_named_constant_in_rewrite.carbon
|
|
library "[[@TEST_NAME]]";
|
|
|
|
interface I {
|
|
let X: type;
|
|
let Y: type;
|
|
}
|
|
|
|
fn Test() {
|
|
// CHECK:STDERR: fail_todo_named_constant_in_rewrite.carbon:[[@LINE+4]]:15: error: semantics TODO: `local generic `let` bindings are currently unsupported` [SemanticsTodo]
|
|
// CHECK:STDERR: let generic Constant: type = ();
|
|
// CHECK:STDERR: ^~~~~~~~~~~~~~
|
|
// CHECK:STDERR:
|
|
let generic Constant: type = ();
|
|
|
|
fn F(generic T: I where .X = Constant) {}
|
|
|
|
fn G(generic T: I where .X = Constant) {
|
|
// TODO: The facet type T in G should match the facet type T in F.
|
|
F(T);
|
|
}
|
|
}
|
|
|
|
// --- fail_todo_named_constant_two_levels_in_rewrite.carbon
|
|
library "[[@TEST_NAME]]";
|
|
|
|
interface I {
|
|
let X: type;
|
|
let Y: type;
|
|
}
|
|
|
|
fn Test() {
|
|
// CHECK:STDERR: fail_todo_named_constant_two_levels_in_rewrite.carbon:[[@LINE+4]]:15: error: semantics TODO: `local generic `let` bindings are currently unsupported` [SemanticsTodo]
|
|
// CHECK:STDERR: let generic Constant2: type = ();
|
|
// CHECK:STDERR: ^~~~~~~~~~~~~~~
|
|
// CHECK:STDERR:
|
|
let generic Constant2: type = ();
|
|
let generic Constant: type = (Constant2, );
|
|
|
|
fn F(generic T: I where .X = Constant) {}
|
|
|
|
fn G(generic T: I where .X = Constant) {
|
|
// TODO: The facet type T in G should match the facet type T in F.
|
|
F(T);
|
|
}
|
|
}
|
|
|
|
// --- fail_todo_named_constant_in_rewrite_callee.carbon
|
|
library "[[@TEST_NAME]]";
|
|
|
|
interface I {
|
|
let X: type;
|
|
let Y: type;
|
|
}
|
|
|
|
fn Test() {
|
|
// CHECK:STDERR: fail_todo_named_constant_in_rewrite_callee.carbon:[[@LINE+4]]:15: error: semantics TODO: `local generic `let` bindings are currently unsupported` [SemanticsTodo]
|
|
// CHECK:STDERR: let generic Constant: type = ();
|
|
// CHECK:STDERR: ^~~~~~~~~~~~~~
|
|
// CHECK:STDERR:
|
|
let generic Constant: type = ();
|
|
|
|
fn F(generic T: I where .X = Constant) {}
|
|
|
|
fn G(generic T: I where .X = ()) {
|
|
// TODO: The facet type T in G should match the facet type T in F.
|
|
F(T);
|
|
}
|
|
}
|
|
|
|
// --- fail_todo_named_constant_in_rewrite_caller.carbon
|
|
library "[[@TEST_NAME]]";
|
|
|
|
interface I {
|
|
let X: type;
|
|
let Y: type;
|
|
}
|
|
|
|
fn Test() {
|
|
// CHECK:STDERR: fail_todo_named_constant_in_rewrite_caller.carbon:[[@LINE+4]]:15: error: semantics TODO: `local generic `let` bindings are currently unsupported` [SemanticsTodo]
|
|
// CHECK:STDERR: let generic Constant: type = ();
|
|
// CHECK:STDERR: ^~~~~~~~~~~~~~
|
|
// CHECK:STDERR:
|
|
let generic Constant: type = ();
|
|
|
|
fn F(generic T: I where .X = ()) {}
|
|
|
|
fn G(generic T: I where .X = Constant) {
|
|
// TODO: The facet type T in G should match the facet type T in F.
|
|
F(T);
|
|
}
|
|
}
|
|
|
|
// --- fail_todo_named_constant_in_nested_facet_type.carbon
|
|
library "[[@TEST_NAME]]";
|
|
|
|
interface I {
|
|
let X: type;
|
|
let Y: type;
|
|
}
|
|
|
|
fn Test() {
|
|
// CHECK:STDERR: fail_todo_named_constant_in_nested_facet_type.carbon:[[@LINE+4]]:15: error: semantics TODO: `local generic `let` bindings are currently unsupported` [SemanticsTodo]
|
|
// CHECK:STDERR: let generic Constant: type = ();
|
|
// CHECK:STDERR: ^~~~~~~~~~~~~~
|
|
// CHECK:STDERR:
|
|
let generic Constant: type = ();
|
|
|
|
// TODO: The .Self reference in each .X should be different, there should be
|
|
// no cycle here.
|
|
fn F(generic T: I where .X = (I where .X = Constant)) {}
|
|
|
|
fn G(generic T: I where .X = (I where .X = Constant)) {
|
|
// TODO: The facet type T in G should match the facet type T in F.
|
|
F(T);
|
|
}
|
|
}
|
|
|
|
// --- fail_todo_named_constant_in_nested_facet_type_caller.carbon
|
|
library "[[@TEST_NAME]]";
|
|
|
|
interface I {
|
|
let X: type;
|
|
let Y: type;
|
|
}
|
|
|
|
fn Test() {
|
|
// CHECK:STDERR: fail_todo_named_constant_in_nested_facet_type_caller.carbon:[[@LINE+4]]:15: error: semantics TODO: `local generic `let` bindings are currently unsupported` [SemanticsTodo]
|
|
// CHECK:STDERR: let generic Constant: type = ();
|
|
// CHECK:STDERR: ^~~~~~~~~~~~~~
|
|
// CHECK:STDERR:
|
|
let generic Constant: type = ();
|
|
|
|
fn F(generic T: I where .X = (I where .X = ())) {}
|
|
|
|
// TODO: The .Self reference in each .X should be different, there should be
|
|
// no cycle here.
|
|
fn G(generic T: I where .X = (I where .X = Constant)) {
|
|
// TODO: The facet type T in G should match the facet type T in F.
|
|
F(T);
|
|
}
|
|
}
|
|
|
|
// --- fail_named_constant_in_nested_facet_type_callee.carbon
|
|
library "[[@TEST_NAME]]";
|
|
|
|
interface I {
|
|
let X: type;
|
|
let Y: type;
|
|
}
|
|
|
|
fn Test() {
|
|
// CHECK:STDERR: fail_named_constant_in_nested_facet_type_callee.carbon:[[@LINE+4]]:15: error: semantics TODO: `local generic `let` bindings are currently unsupported` [SemanticsTodo]
|
|
// CHECK:STDERR: let generic Constant: type = ();
|
|
// CHECK:STDERR: ^~~~~~~~~~~~~~
|
|
// CHECK:STDERR:
|
|
let generic Constant: type = ();
|
|
|
|
// TODO: The .Self reference in each .X should be different, there should be
|
|
// no cycle here.
|
|
fn F(generic T: I where .X = (I where .X = Constant)) {}
|
|
|
|
fn G(generic T: I where .X = (I where .X = ())) {
|
|
// TODO: The facet type T in G should match the facet type T in F.
|
|
F(T);
|
|
}
|
|
}
|