nx_field_of_struct_gate.nx

nx_field_of_struct_gate.nx -- LN29 (lang.plan, 2026-09-02): A FIELD NAME MUST BELONG TO THE STRUCT IT IS READ FROM. End-to-end over the PROMOTED compiler: two fixtures are assembled at runtime in /tmp/<gate>/ (never a file a source census could mistake for an organ), the compiler is forked on each with stderr captured to a file, and the teeth read the captured bytes: fx_bad reads p.c on a struct declaring a and b -> MUST be refused, naming the struct, the field and the fields it really declares (the teaching voice: where, caret, why, fix) fx_ok reads p.a and p.b on the same struct -> MUST compile with no error line (the positive control) The refusal is the LN29 contract; the control is what keeps the gate from passing on a compiler that refuses everything. The "corpus builds unchanged" half of the done-rule is nx_cc_equiv_gate's job (10 rows + self-host), deliberately not duplicated here (one ruler per question). nx_field_of_struct_gate -- verdict in the exit code (gv_verdict) license_tier: ORIGINAL layer: lang module: nishi-core.lang.field_of_struct_gate