nx_pattern_emit8.nx

nx_pattern_emit8.nx -- PATTERN EMITTER: STRUCT_WALK (shape 13 -- race-1's first named growth rung: the assignment-DECOMPOSITION step Claude still had to hand-write). Authors a fixed+var field-sequence walker from a FIELD TABLE (the spec is the config, rule 11): kind 0 = FIXED(w) skip w bytes (w from widths[i]) kind 1 = VAR8 1-byte length prefix + body kind 2 = VAR16 2-byte BE length prefix + body kind 3 = TAIL16 2-byte BE length prefix; the walker RETURNS this final block Authored fn: <name>_locate(b, n, out) -> 0 ok (out[0]=block off, out[1]=block len) / -1 = any truncation REFUSED (never a clipped read). The ClientHello layout (hdr/ver/random/sid/suites/ comp/extensions) is exactly this table -- so are the B5 container headers. Per-field bounds checks + offsets are BAKED at emit time field-by-field; the core has no table interpreter at runtime (composition of straight-line checks, rule 22). Test KATs are COMPUTED BY THE EMITTER from a synthetic image it constructs to the same table (exact off/len + truncation refusal). REFUSAL RAILS: unknown kind, TAIL16 not last, last not TAIL16, FIXED width < 1, nfields < 1 -> spec REFUSED, never authored. Extends emit chain ..emit7(WIRE_TLV). LAWS: struct-free, integer-only, flat ifs, no &&/||, <=6 args per func. license_tier: ORIGINAL