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Chandler Carruthandjosh11b
7871237c15
Implements proposal #7016: `self` moves from the deduced implicit list (`fn F[self: Self]()`) to the front of the explicit list. Its type may be written explicitly (`fn F(self: Self)`) or omitted, in which case it defaults to `Self` (`fn F(self)`, `fn F(ref self)`); `self` in the implicit list is rejected. Throughout checking, `self` is modeled as the first explicit parameter. Because a method is just a function whose first parameter is `self`, it can also be called as an ordinary function with the receiver passed explicitly (`Type.M(obj, ...)`), not only as `obj.M(...)`. A new `SemIR::CallArgParamPatterns` helper chooses the parameters matched against the explicit arguments, excluding a leading `self` only when it is supplied as a method-call receiver; arity checking, conversion, and generic deduction use it. The resulting SemIR and lowering are unchanged: `self` is still `call_param0`, and witnesses, thunks, and vtables are unaffected. An omitted `self` type is parsed as a `SelfBindingPattern` node with no type expression; checking synthesizes the `Self` type so it behaves exactly like `self: Self`. However, the exact spelling used must match between a forward declaration and a definition, following #3763's rules around declaration matching. Generated functions, thunks, and C++ interop import/export build `self` as the first explicit parameter, and the `self`-type override (e.g. Derived->Base for a virtual override) applies to the explicit `self`. Placement is validated by new diagnostics: `SelfInImplicitParamList`, `SelfNotFirstParam`, and `SelfOutsideParamList`. The benchmark source generator and the documentation adopt the `(self)` shorthand; the prelude, the examples, and the test data are migrated in the following commits. Assisted-by: Claude Code with Claude Opus 4.7 --------- Co-authored-by: josh11b <15258583+josh11b@users.noreply.github.com>
39 lines
2.2 KiB
Plaintext
39 lines
2.2 KiB
Plaintext
// 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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//
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// AUTOUPDATE
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// TIP: To test this file alone, run:
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// TIP: bazel test //toolchain/testing:file_test --test_arg=--file_tests=toolchain/parse/testdata/generics/impl/basic.carbon
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// TIP: To dump output, run:
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// TIP: bazel run //toolchain/testing:file_test -- --dump_output --file_tests=toolchain/parse/testdata/generics/impl/basic.carbon
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impl i32 as Interface {
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fn Add(self, b: Self) -> Self;
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}
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// CHECK:STDOUT: - filename: basic.carbon
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// CHECK:STDOUT: parse_tree: [
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// CHECK:STDOUT: {kind: 'FileStart', text: ''},
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// CHECK:STDOUT: {kind: 'ImplIntroducer', text: 'impl'},
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// CHECK:STDOUT: {kind: 'IntTypeLiteral', text: 'i32'},
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// CHECK:STDOUT: {kind: 'ImplTypeAs', text: 'as', subtree_size: 2},
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// CHECK:STDOUT: {kind: 'IdentifierNameExpr', text: 'Interface'},
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// CHECK:STDOUT: {kind: 'ImplDefinitionStart', text: '{', subtree_size: 5},
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// CHECK:STDOUT: {kind: 'FunctionIntroducer', text: 'fn'},
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// CHECK:STDOUT: {kind: 'IdentifierNameMaybeBeforeSignature', text: 'Add'},
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// CHECK:STDOUT: {kind: 'ExplicitParamListStart', text: '('},
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// CHECK:STDOUT: {kind: 'SelfValueName', text: 'self'},
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// CHECK:STDOUT: {kind: 'SelfBindingPattern', text: 'self', subtree_size: 2},
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// CHECK:STDOUT: {kind: 'PatternListComma', text: ','},
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// CHECK:STDOUT: {kind: 'IdentifierNameNotBeforeSignature', text: 'b'},
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// CHECK:STDOUT: {kind: 'SelfTypeNameExpr', text: 'Self'},
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// CHECK:STDOUT: {kind: 'LetBindingPattern', text: ':', subtree_size: 3},
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// CHECK:STDOUT: {kind: 'ExplicitParamList', text: ')', subtree_size: 8},
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// CHECK:STDOUT: {kind: 'SelfTypeNameExpr', text: 'Self'},
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// CHECK:STDOUT: {kind: 'ReturnType', text: '->', subtree_size: 2},
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// CHECK:STDOUT: {kind: 'FunctionDecl', text: ';', subtree_size: 13},
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// CHECK:STDOUT: {kind: 'ImplDefinition', text: '}', subtree_size: 19},
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// CHECK:STDOUT: {kind: 'FileEnd', text: ''},
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// CHECK:STDOUT: ]
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