7f3bd69bd9
Any assignment / compound-assignment whose target chain is ROOTED at a
constant — a const-flagged global (array consts, #run consts) or a
module value const (struct consts incl.) — diagnoses 'cannot assign
through constant X' at compile time. A struct const's field write used
to compile and bus-error at runtime (issue 0116); scalars misfired
silently. A deref along the chain (p.*) breaks the root — pointer
writes stay the documented escape until the const-ness steps; a local
shadowing the const name stays writable.
Also: typed struct constants ('W : Color : Color.{...}') register —
the shape list skipped struct_literal, leaving the typed form
unresolved while the untyped one worked.
Examples: 1162 (all rejection shapes incl. the 0116 crash repro),
0178 (typed struct const reads + copy independence).
17 lines
513 B
Plaintext
17 lines
513 B
Plaintext
// A TYPED struct constant ('W : Color : Color.{...}') registers like the
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// untyped form ('WHITE :: Color.{...}') — value reads, field reads, and
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// independent copies. (Both shapes keep inline re-lowering semantics
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// until PLAN-CONST-AGG step 4 migrates them to const globals.)
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#import "modules/std.sx";
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Color :: struct { r, g, b: s64; }
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W : Color : Color.{ r = 1, g = 2, b = 3 };
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main :: () {
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print("{} {} {}\n", W.r, W.g, W.b);
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c := W;
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c.g = 99;
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print("copy={} const={}\n", c.g, W.g);
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}
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