Emit bounded documented instructions for scalar assignments, word and integer
arithmetic, comparisons, and short-circuit booleans, with checked forward
branch fixups. Add multiply and signed/unsigned divide helpers with a stable
divide-by-zero result, plus a reviewed golden byte stream and disassembly.

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Implement transactional frame entry/leave, right-to-left arguments, one- and
two-byte returns, and guards for both the software stack and the 6502 hardware
stack. Add a recursive x128 ABI fixture covering bounded success and overflow
unwind.

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Emit a BASIC-stub PRG with ordered sections and a MAP entry/section table,
refuse existing output names, and scratch partial files on failure. Include
a runnable startup that reports through the test mailbox.

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Number interface methods in source order and check each class against every
implemented interface, reporting missing, private, mismatched, conflicting,
and non-interface implementations at the class declaration.

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Compute sizes and offsets after the declaration pass so forward references
have a kind, report E096 for instances over 65535 bytes, and record the
layout in the parser harness so declaration order is fixture-checked.

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types.s gives every expression a type and applies the spec 3.4/8
conversions, operator table, constant folding and diagnostic spellings.
parser.s records implements lists and init rows in pass 1, carries types
through member chains, groups, calls and indexing in pass 2, and checks
assignments, arguments, returns, conditions, for, print, delete and member
access. A method that declares a result must end in return; a missing one
is E150 at end, and a program return value is E151.

Three older parser fixtures gain true diagnostics. The lexer's host
reference formatter now spells bytes such as {0D} correctly, and the demo
tolerates a missing ERR file.

Verified in x128: 37 parser fixtures, 10 lexer fixtures, the 67-entry
diagnostic catalog, and the Vim-to-N8CHECK demo (good.n8 clean, bad.n8's
four diagnostics).

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parse_statement parses every spec 7 form (assignment, call, if/else,
while, for/to/step, return, print, delete) and requires the line to end
after it. Expressions use precedence climbing over spec 8's levels: binary
operators left associative, unary not and - nesting rightwards, postfix
member access, calls, and indexing tightest. A syntax error is reported in
pass 1, unwinds to the statement, and skips the line; E03-S02's name,
member, and access checks now run from the parser in pass 2, replacing the
token scan. Expression nesting is bounded at 16 levels (E225).

Verified in x128: 31 fixtures, including the two statement fixtures that
were pending since E03-S01, a postfix trace golden for precedence and
associativity (both mutations caught), every statement form, and 15
independent syntax errors with recovery. Lowest stack pointer $A7. New
diagnostics E038-E042 and E225. The demo passes; its Vim typing is slowed
to 200 ms per key after one doubled keystroke.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/demo-write-check.ps1 types each demo program into the Vim clone
on x64sc (fresh copy of vim/work.d81), confirms the saved SEQ file matches
its ASCII mirror, then runs demo/n8check.s on x128: a DEMO driver (not
N128C) that asks for a file name and runs the current front end (source
reader, lexer, names, parser) with on-screen diagnostics and NAME.ERR.
good.n8 checks clean; bad.n8 reports its four intended errors.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Pass 1 now records every field and method signature (access, type,
parameter types) in bank-1 member and parameter tables, rejects duplicate
fields or methods per type, invalid init/destroy shapes (E151/E152, D122),
and `var` after a method statement or inside a block. Each signature and the
program open a typed local scope. Pass 2 scans statement lines: unqualified
names must be locals, parameters, or fields of the enclosing class (D123),
and member chains through locals, fields, self, new, calls, and indexing
report unknown members (E061) and private access (E120) at the member.

The parser test PRG grew past $4000 and crashed: mmu_init copies the COMMON
load image in the system mapping, where BASIC ROM hides $4000+. COMMON now
loads right after STARTUP and mmu.s asserts both stay below $4000.

Verified in x128: 28 fixtures, member tables against a source-derived
oracle, privacy and scope mutations caught; map, source, lexer, names, and
diagnostics suites pass on the new layout.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

parser.s runs two passes over the cached source. Pass 1 parses interfaces,
classes (implements lists, fields, method headers), and the one program,
records top-level types in a bank-1 table, tracks method/program/if/while/
for blocks, checks duplicate locals, and reports syntax, ordering, and
duplicate errors with line-level recovery. Pass 2 reports type references
that name no declared type, so forward references are legal.

Verified in x128 against 24 fixtures through the real ERR files: 7/7
accepted, 10/12 rejected grammar fixtures at their sidecar positions
(line_cont and multi_stmt are statement-level, pending E03-S03), and five
parser fixtures matching their complete diagnostic lists. A pass-order
mutation is caught. D121 (proposed): method names may be keywords, as
spec 5.1's `method print()` requires.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

diagcat.inc is the single catalog: one line per diagnostic with a stable
number in a per-category range. Included by errors.inc it gives E_*
constants; included by diagnostics.s it gives the message table.
docs/diagnostics.md is generated from it. The build rejects out-of-range
or duplicate numbers and any grammar .expect symbol missing from it.

diagnostics.s prints a two-line, 40-column-safe screen form and appends
full lines to NAME.ERR. NAME.ERR is scratched at the start and created
only when needed. After 20 errors, E221 replaces the next one and the
caller must stop. diskio.s gains output-file and DOS-command wrappers.

Verified in x128: screen RAM rows, diag.err and limit.err read back from
the D81, stale-file scratching, an unwritable ERR name (DOS 33 -> E201
once), and no open files after any phase. A counting mutation is caught.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

names.s gives each distinct identifier a 1-byte ID (1-255), comparing
case-insensitively across both PETSCII letter ranges. The table lives in
bank 1: 64 hash-chain heads plus 20-byte records holding the original
spelling. name_declare replaces the first-use spelling with the first
declaration's spelling, so forward references keep the declared form.
A full table returns NAMES_ERR_FULL and writes nothing.

Verified in x128: the C128 dump equals a host model byte for byte across
case variants, an 8-name collision chain with an identical-hash pair, and
a 260-name overflow, with a guard after the table intact. A mutation that
skips the text compare is caught. D120 (proposed): 255-name limit.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

lexer.s turns cached source lines into tokens with stable kinds and error
codes (tokens.inc): 32 keywords, identifiers folded across both PETSCII
letter ranges, decimal/hex/binary numbers to 65535, strings and character
literals with escapes, all operators, and comments. An error reports its
exact column, then the rest of the line is skipped.

An independent host reference lexer and the C128 lexer in x128 both
reproduce the reviewed golden token files: 10 fixtures, 1,119 tokens,
including one fixture per error kind. A case-folding mutation is caught.

Spec 2.2 now lists <= and >=, matching section 8. D119 (proposed): the \n
and \r escapes both produce $0D. The monitor helper now reads RAM bank 0,
because BASIC ROM hides $4000+ after a program returns.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src_load reads a SEQ file from device 8 once into a bank-1 cache (D118).
It enforces the 80-byte line, 599-line, and 18,999-byte limits as bytes
arrive and reports stable codes with exact positions. src_rewind and
src_next_line replay the cache one logical line at a time for every pass.
diskio.s wraps the KERNAL file calls; channels close on every path.

Verified in x128 with a 1581: eight fixtures, including the exact limits,
each limit error, a missing file (DOS 62), and a missing final $0D, all
match host-computed line counts, Fletcher-16 checksums, and positions.
Adds a shared PowerShell test library for x128 scripts.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Add cfg/compiler.cfg, the production mmu.s, c128.inc, and the test mailbox,
proven by a capacity-checking skeleton in x128:

- 8K bottom common RAM, shared code at $1300, private zero page at bank 0
  page $1A via P0, bank-1 tables at $2000-$BFFF, test mailbox at $1BF0
- ld65 rejects overflows of the ZP, COMMON, MAIN, SWSTACK, and TABLES areas
- a CIA #2 timer NMI taken under bank 1 with the private zero page returns
  cleanly through the NMI guard (closes the E01-S03 NMI risk)
- decision D117 records the map; RESTORE is ignored while compiling

Also pin newLang/ to LF in .gitattributes. A branch switch under
core.autocrlf had rewritten the byte-exact fixtures with CRLF.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Nova128 is an object-oriented language with an on-machine C128 compiler.
This adds the spec, decisions, architecture, backlog, and story claims,
plus the grammar fixtures (E00-S02), disk-image builder (E07-S01), and
the x128-verified platform probes:

- E01-S01 minimal native PRG
- E01-S02 MMU/common-RAM probe. With bottom common on, a P0/P1 pointer
  aimed at bank 1 lands in bank 0 at the translated page. The verifier
  traces every MMU write in the probe window.
- E01-S03 KERNAL wrapper (kcall). CHROUT, drive status, and a
  device-not-present failure work from bank 0 and bank 1 mappings.
  A/X/Y/C/ST are preserved and the MMU state is restored exactly.
- E01-S04 40/80-column display and clock probe

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>