004 reject write on view

✓ Passing This code compiles and runs correctly.

Code

// PIN (enforcement): append demands <instance>; calling it on a <view!>
// is a phantom state mismatch. Write access requires taking ownership.
~import std/string

~std/string:from-page(text: "hello")
| ok s |> std/string:append(s, text: " world")
    | ok |> std/string:free(s)
    | err _ |> std/string:free(s)
| err _ |> _

input.kz

Must contain:

Phantom state mismatch

Error Verification

Actual Compiler Output

error[KORU030]: Phantom state mismatch: expected 'std.string:instance' but got 'std.string:view!' for argument 's'
  --> phantom_semantic_check:6:0

❌ Compiler coordination error: Phantom semantic validation failed
error: CompilerCoordinationFailed
/Users/larsde/src/koru/tests/regression/600_STDLIB/610_STRING/610_004_reject_write_on_view/backend.zig:94:13: 0x10084e3b3 in emit (backend)
            return error.CompilerCoordinationFailed;
            ^
/Users/larsde/src/koru/tests/regression/600_STDLIB/610_STRING/610_004_reject_write_on_view/backend.zig:190:28: 0x10084f09f in main (backend)
    const generated_code = try RuntimeEmitter.emit(compile_allocator, final_ast);
                           ^

Test Configuration

MUST_FAIL

← 003 auto free unused string 005 reject use after free →