b48766d153
A generic struct can take a pack type-param ..$Ts: []Type that binds the remaining type args as a sequence, and a pack-shaped tuple field (..$Ts) resolves to a tuple of those per-position types. - parser/ast: accept a leading .. on a struct generic param; StructTypeParam gains is_variadic. - registration: TemplateParam carries is_variadic (and is a type param). - instantiateGenericStruct: a variadic type-param consumes the remaining args into pack_bindings + pack_arg_types (mangled into the name); restored after. - resolveTypeWithBindings: a tuple-literal-as-type containing a pack spread (e.g. (..$Ts)) expands via packTypeElems. Instantiate + correct per-position field types + whole-tuple store + element read all work (examples/205). Not yet: protocol-applied field (..F(Ts)) (the canonical (..VL(Ts)) shape) and nested element assignment b.pair.0 = v. 240 examples + unit green.
26 lines
964 B
Plaintext
26 lines
964 B
Plaintext
// Phase 4.2 (core) — a generic struct with a pack type-param `..$Ts: []Type`
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// and a pack-shaped tuple field `(..$Ts)`. Each instantiation binds the
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// remaining type args as the pack, so the field is a tuple of those per-position
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// types. Storing the whole tuple field and reading its elements both work.
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#import "modules/std.sx";
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Box :: struct($R: Type, ..$Ts: []Type) {
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r: $R;
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pair: (..$Ts); // tuple of the pack's element types
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}
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main :: () -> s32 {
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// Box(s64, s32, string): R=s64, Ts=[s32, string], pair: (s32, string).
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a : Box(s64, s32, string) = ---;
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a.r = 7;
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a.pair = (42, "hi"); // whole-tuple field store
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print("a: r={} 0={} 1={}\n", a.r, a.pair.0, a.pair.1);
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// A different shape → a different per-position tuple field.
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b : Box(bool, string, bool) = ---; // Ts=[string, bool], pair: (string, bool)
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b.pair = ("x", true);
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print("b: 0={} 1={}\n", b.pair.0, b.pair.1);
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0;
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}
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