New: wasm/tests/parity-cross-tier.mjs runs the parity-corpus.mjs (216
test cases tagged by whitepaper section / R7RS concept) against three
tiers — native python (reference), c-wasm, asm-wasm — and fails on any
unknown divergence. Known gaps live in KNOWN_DIVERGE so the table stays
green while the bignum / call/cc / etc. work proceeds.
Wired into `make wasm-test` so a regression against any spec claim gets
caught before merge.
Bugs caught and fixed:
- python remainder: was `signed_a % signed_b * sign(a)`, which double-
applied the sign of a (python's % floors) — gave -3 for (-17, 5)
instead of the R7RS-correct -2. Now uses abs() on both sides.
- asm-wasm modulo: was i32.rem_s (truncated, remainder semantics)
where R7RS modulo wants sign of divisor. Added the "if rem and
divisor disagree on sign, add divisor" branch.
Cross-tier numbers after fix:
216 passing
3 known diverge: expt-2-100, expt-3-50, big-arith — all asm-wasm
(no bignums on the asm tier yet; whitepaper §2.1 claim still open)
0 fail
REPL layout: body is now the scroll container, prompt-bar is
position:fixed at the viewport bottom so it doesn't get pushed off
screen by a long transcript. Empty space above the prompt on a fresh
session reads like a terminal.
All other tests still pass: 20 unit, 8 integration, 11 functional.
Adds tag-9 rational type to the asm tier. Layout [tag=9, num:i32, den:i32].
make_rational normalizes via gcd and collapses to a fixnum when den
reduces to 1, so 14/2 stays as 7.
Arithmetic (+, -, *, /, =, <, >, <=, >=) now promotes to rational when
any argument is rational. Mixed fixnum/rational lifts the fixnum
accumulator into a rational mid-loop so (+ 1 1/2) returns 3/2, not 1/2.
Reader parses "67/7" literals via the existing atom path: after the
numerator's digits, if '/' follows we keep reading the denominator and
hand back a normalized rational. Falls through to symbol if either side
isn't all digits.
Printer renders rationals as "n/d". equal_p compares numbers by value
(1/2 = 2/4, 3 = 6/2). is_number / number? cover both fixnums and
rationals.
eval now treats rationals as self-evaluating — without this, '1/3'
parsed correctly but evaluated to VOID.
Mandelbrot demo: switched from (/ a b) to (quotient a b) for the
fixed-point math. The demo had been relying on integer truncation
that '/' no longer provides on tiers with R7RS-correct rationals.
Bignums still pending: 31-bit num/den overflows with huge denominators.
Real lift comes with the bignum task in the C tier (which has them) or
a new bignum module in the WAT.
Cross-tier check still hangs on the bigger TCO-heavy sections of
functional.lsp — separate from rationals. Will keep grinding.
Tests: unit 20/20, integration 8/8, functional 11/11.
Interactive REPL at lumbda.com/repl with:
- multi-tab sessions (click + to add, × to close, double-click to rename)
- per-tab tier selector (python/c/asm/all-three race)
- persistent transcripts encrypted in localStorage via Web Crypto
(PBKDF2 + AES-GCM, vault id = SHA-256(password || device-salt) —
same pattern as unsandbox's vault-encryption-design.md, native
crypto.subtle API instead of CryptoJS)
- ephemeral mode (skip vault, transcripts vanish on reload)
- one worker per (tab × tier) — state persists across evals in a tab
- reboot tier button (terminate this tab's worker, fresh state next eval)
- cancel button (kills the running worker in active tab)
Home page now links to both /playground/ and /repl/.
Tier state itself does NOT persist across reloads — the transcript does,
but defines/set!/hash-tables vanish with the worker. Portal save/resume
in WAT (deferred) will let a tier session survive close+reopen.
