nx_normdiff.nx

nx_normdiff.nx -- IS THIS DIFFERENCE MADE OF CODE, OR OF COSMETICS? The escalation ruler. WHY IT EXISTS. nx_srcdiff answers "is a direction merge safe?" on the RAW line multiset, and that strictness is correct as a GUARD -- it is what caught the escaped nx_media_extract mutant that a symbol-set ruler waved through. But as a CENSUS it overstates the fork: it reports BIDIRECTIONAL for two files that differ only because a NAS cron lifted `4096` into `FOO_MAGIC_4096`, or because one side carries a trailing `// why` comment the other lacks. Measured on the standing residual: the raw ruler could decide 3.6% of 3,073 forked files; normalising first decides 8.6%. The other 91% is REAL CODE -- surplus shapes censused as control-flow 1408, bindings 1042, func-decls 278 -- which is the finding that matters most: NO FURTHER NORMALISER WILL CRACK IT, so stop building them. => ★A RULER TUNED TO BE A SAFE GUARD IS THE WRONG RULER FOR A CENSUS. Report BOTH verdicts and let the caller pick: the guard decides whether to ACT, the census decides what to LOOK AT. WHAT IT NORMALISES, and nothing else: 1. a trailing `//` comment -- ONLY when outside a string literal (backslash-escape aware, so `"http://x"` and `"a\"b // c"` are not mistaken for comments) 2. runs of whitespace -> one space; leading/trailing stripped 3. a const identifier -> ITS DECLARED VALUE TEXT, read out of the file that declares it. !!THE OBVIOUS SHORTCUT IS UNSOUND, measured: reading the digits out of `FOO_MAGIC_4096` breaks on nx_lz4_header's `const LZ4_MAGIC_0: i64 = 0x04` and nx_nxtask_store's `NXT_MAGIC_0 = 0x4E`. There the trailing digit is a FIELD INDEX ("magic byte 0"), and the value is an unrelated hex byte. A name-digit un-lift equates 0 with 4 and calls two different files identical. ⇒ ★A NAMING CONVENTION IS A COMMENT: IT IS EVIDENCE ABOUT INTENT, NEVER ABOUT VALUE. The value is substituted as its DECLARED TEXT, verbatim and unparsed. That is deliberate: a parser that "helpfully" normalised 0x04 to 4 would need to be right about every literal form in the language, and being wrong about one is how the line above got mis-measured TWICE (a decimal regex silently matched the `0` out of `0x04` and reported the const as declared zero). ⇒ ★DON'T PARSE WHAT YOU ONLY NEED TO COMPARE. WHERE THE TABLE COMES FROM, and why there is no tree walk here: NishiLang requires consts above use, and the NAS magicsweep lifts a literal into a const IN THE SAME FILE. Measured across both trees: 3,728 of 3,730 lifted-const uses (99.946%) are declared in the file that uses them -- the only two exceptions tree-wide are nx_archive_server's K_MAGIC_8080 and nx_web_crawl_step_gate's WC_MAGIC_2048. So each side's table is built FROM THAT SIDE'S OWN SOURCE, which is also the semantically correct scope: a const means what ITS file declares it to mean. Two files that declare the same name differently therefore normalise DIFFERENTLY and stay visible as surplus, which a single shared table would have silently equated. ⇒ ★A SYMBOL'S MEANING IS SCOPED; A LOOKUP TABLE THAT FORGETS THE SCOPE INVENTS AGREEMENT. [consttab] remains as an optional FALLBACK for the cross-file residual; file-local always wins.