carbon-language/carbon-lang
1
0
Fork 0
mirror of https://github.com/carbon-language/carbon-lang.git synced 2026-10-05 22:02:55 +01:00
Code Issues Packages Projects Releases 10 Wiki Activity

Replace :! binding syntax with phase keywords and contextual defaults (#7479)

Browse Source 
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
This commit is contained in:
Chandler Carruth
2026-07-11 01:22:44 +00:00
committed by GitHub
parent bf106c3b4b
commit 8be274cf60
482 changed files with 16917 additions and 16226 deletions
Download Patch File Download Diff File Expand all files Collapse all files
toolchain/check/testdata/function/generic/import_specific.carbon
Vendored
+26 -26
View File
@@ -16,10 +16,10 @@
library "[[@TEST_NAME]]";
fn F(unused T:! type) {
fn F(unused generic T: type) {
}
fn G(T:! type) {
fn G(generic T: type) {
F(T);
}
@@ -62,28 +62,28 @@ fn H() {
// CHECK:STDOUT: .G = %G.decl
// CHECK:STDOUT: }
// CHECK:STDOUT: %F.decl: %F.type = fn_decl @F [concrete = constants.%F] {
// CHECK:STDOUT: %T.patt.loc4_14.1: %pattern_type = symbolic_binding_pattern T, 0 [symbolic = %T.patt.loc4_14.2 (constants.%T.patt.d47011.1)]
// CHECK:STDOUT: %T.patt.loc4_22.1: %pattern_type = symbolic_binding_pattern T, 0 [symbolic = %T.patt.loc4_22.2 (constants.%T.patt.d47011.1)]
// CHECK:STDOUT: } {
// CHECK:STDOUT: %.loc4_17.1: type = splice_block %.loc4_17.2 [concrete = type] {
// CHECK:STDOUT: %.loc4_24.1: type = splice_block %.loc4_24.2 [concrete = type] {
// CHECK:STDOUT: %.Self.frozen: %type = symbolic_binding .Self [symbolic_self = constants.%.Self.frozen]
// CHECK:STDOUT: %.loc4_17.2: type = type_literal type [concrete = type]
// CHECK:STDOUT: %.loc4_24.2: type = type_literal type [concrete = type]
// CHECK:STDOUT: }
// CHECK:STDOUT: %T.loc4_14.2: type = symbolic_binding T, 0 [symbolic = %T.loc4_14.1 (constants.%T.67db0b.1)]
// CHECK:STDOUT: %T.loc4_22.2: type = symbolic_binding T, 0 [symbolic = %T.loc4_22.1 (constants.%T.67db0b.1)]
// CHECK:STDOUT: }
// CHECK:STDOUT: %G.decl: %G.type = fn_decl @G [concrete = constants.%G] {
// CHECK:STDOUT: %T.patt.loc7_7.1: %pattern_type = symbolic_binding_pattern T, 0 [symbolic = %T.patt.loc7_7.2 (constants.%T.patt.d47011.2)]
// CHECK:STDOUT: %T.patt.loc7_15.1: %pattern_type = symbolic_binding_pattern T, 0 [symbolic = %T.patt.loc7_15.2 (constants.%T.patt.d47011.2)]
// CHECK:STDOUT: } {
// CHECK:STDOUT: %.loc7_10.1: type = splice_block %.loc7_10.2 [concrete = type] {
// CHECK:STDOUT: %.loc7_17.1: type = splice_block %.loc7_17.2 [concrete = type] {
// CHECK:STDOUT: %.Self.frozen: %type = symbolic_binding .Self [symbolic_self = constants.%.Self.frozen]
// CHECK:STDOUT: %.loc7_10.2: type = type_literal type [concrete = type]
// CHECK:STDOUT: %.loc7_17.2: type = type_literal type [concrete = type]
// CHECK:STDOUT: }
// CHECK:STDOUT: %T.loc7_7.2: type = symbolic_binding T, 0 [symbolic = %T.loc7_7.1 (constants.%T.67db0b.2)]
// CHECK:STDOUT: %T.loc7_15.2: type = symbolic_binding T, 0 [symbolic = %T.loc7_15.1 (constants.%T.67db0b.2)]
// CHECK:STDOUT: }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: generic fn @F(%T.loc4_14.2: type) {
// CHECK:STDOUT: %T.patt.loc4_14.2: %pattern_type = symbolic_binding_pattern T, 0 [symbolic = %T.patt.loc4_14.2 (constants.%T.patt.d47011.1)]
// CHECK:STDOUT: %T.loc4_14.1: type = symbolic_binding T, 0 [symbolic = %T.loc4_14.1 (constants.%T.67db0b.1)]
// CHECK:STDOUT: generic fn @F(%T.loc4_22.2: type) {
// CHECK:STDOUT: %T.patt.loc4_22.2: %pattern_type = symbolic_binding_pattern T, 0 [symbolic = %T.patt.loc4_22.2 (constants.%T.patt.d47011.1)]
// CHECK:STDOUT: %T.loc4_22.1: type = symbolic_binding T, 0 [symbolic = %T.loc4_22.1 (constants.%T.67db0b.1)]
// CHECK:STDOUT:
// CHECK:STDOUT: !definition:
// CHECK:STDOUT:
@@ -95,17 +95,17 @@ fn H() {
// CHECK:STDOUT: }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: generic fn @G(%T.loc7_7.2: type) {
// CHECK:STDOUT: %T.patt.loc7_7.2: %pattern_type = symbolic_binding_pattern T, 0 [symbolic = %T.patt.loc7_7.2 (constants.%T.patt.d47011.2)]
// CHECK:STDOUT: %T.loc7_7.1: type = symbolic_binding T, 0 [symbolic = %T.loc7_7.1 (constants.%T.67db0b.2)]
// CHECK:STDOUT: generic fn @G(%T.loc7_15.2: type) {
// CHECK:STDOUT: %T.patt.loc7_15.2: %pattern_type = symbolic_binding_pattern T, 0 [symbolic = %T.patt.loc7_15.2 (constants.%T.patt.d47011.2)]
// CHECK:STDOUT: %T.loc7_15.1: type = symbolic_binding T, 0 [symbolic = %T.loc7_15.1 (constants.%T.67db0b.2)]
// CHECK:STDOUT:
// CHECK:STDOUT: !definition:
// CHECK:STDOUT: %F.specific_fn.loc8_3.2: <specific function> = specific_function constants.%F, @F(%T.loc7_7.1) [symbolic = %F.specific_fn.loc8_3.2 (constants.%F.specific_fn)]
// CHECK:STDOUT: %F.specific_fn.loc8_3.2: <specific function> = specific_function constants.%F, @F(%T.loc7_15.1) [symbolic = %F.specific_fn.loc8_3.2 (constants.%F.specific_fn)]
// CHECK:STDOUT:
// CHECK:STDOUT: fn() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT: %F.ref: %F.type = name_ref F, file.%F.decl [concrete = constants.%F]
// CHECK:STDOUT: %T.ref: type = name_ref T, %T.loc7_7.2 [symbolic = %T.loc7_7.1 (constants.%T.67db0b.2)]
// CHECK:STDOUT: %T.ref: type = name_ref T, %T.loc7_15.2 [symbolic = %T.loc7_15.1 (constants.%T.67db0b.2)]
// CHECK:STDOUT: %F.specific_fn.loc8_3.1: <specific function> = specific_function %F.ref, @F(constants.%T.67db0b.2) [symbolic = %F.specific_fn.loc8_3.2 (constants.%F.specific_fn)]
// CHECK:STDOUT: %F.call: init %empty_tuple.type = call %F.specific_fn.loc8_3.1()
// CHECK:STDOUT: return
@@ -115,18 +115,18 @@ fn H() {
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: specific @F(constants.%T.67db0b.1) {
// CHECK:STDOUT: %T.patt.loc4_14.2 => constants.%T.patt.d47011.1
// CHECK:STDOUT: %T.loc4_14.1 => constants.%T.67db0b.1
// CHECK:STDOUT: %T.patt.loc4_22.2 => constants.%T.patt.d47011.1
// CHECK:STDOUT: %T.loc4_22.1 => constants.%T.67db0b.1
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: specific @G(constants.%T.67db0b.2) {
// CHECK:STDOUT: %T.patt.loc7_7.2 => constants.%T.patt.d47011.2
// CHECK:STDOUT: %T.loc7_7.1 => constants.%T.67db0b.2
// CHECK:STDOUT: %T.patt.loc7_15.2 => constants.%T.patt.d47011.2
// CHECK:STDOUT: %T.loc7_15.1 => constants.%T.67db0b.2
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: specific @F(constants.%T.67db0b.2) {
// CHECK:STDOUT: %T.patt.loc4_14.2 => constants.%T.patt.d47011.1
// CHECK:STDOUT: %T.loc4_14.1 => constants.%T.67db0b.2
// CHECK:STDOUT: %T.patt.loc4_22.2 => constants.%T.patt.d47011.1
// CHECK:STDOUT: %T.loc4_22.1 => constants.%T.67db0b.2
// CHECK:STDOUT:
// CHECK:STDOUT: !definition:
// CHECK:STDOUT: }
@@ -156,8 +156,8 @@ fn H() {
// CHECK:STDOUT: imports {
// CHECK:STDOUT: %Main.F: %F.type = import_ref Main//library, F, loaded [concrete = constants.%F]
// CHECK:STDOUT: %Main.G: %G.type = import_ref Main//library, G, loaded [concrete = constants.%G]
// CHECK:STDOUT: %Main.import_ref.b3bc94.1: type = import_ref Main//library, loc4_14, loaded [symbolic = @F.%T (constants.%T.67db0b.1)]
// CHECK:STDOUT: %Main.import_ref.b3bc94.2: type = import_ref Main//library, loc7_7, loaded [symbolic = @G.%T (constants.%T.67db0b.2)]
// CHECK:STDOUT: %Main.import_ref.b3bc94.1: type = import_ref Main//library, loc4_22, loaded [symbolic = @F.%T (constants.%T.67db0b.1)]
// CHECK:STDOUT: %Main.import_ref.b3bc94.2: type = import_ref Main//library, loc7_15, loaded [symbolic = @G.%T (constants.%T.67db0b.2)]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {