Param-decl `name: T...` (Tparam.variadic=1, type []T), call-site
gather of N args into a fresh `[N]T`, forward via `xs...`, full
selfhost mirror, and lib/fmt graduated to the Hare shape.
Frontend:
- parse: `T...` after a param's type stamps Node.op=TK_ELLIPSIS
and breaks out (variadic must be last).
- check: resolve_type N_TFN / build_fn_type wrap the param type
as []T and set tp->variadic. N_CALL accepts either a tail of
args assignable to T (gather) or a single `xs...` spread of
[]T (forward); both bypass the "too many args" check on the
variadic slot.
- type: type_eq compares Tparam.variadic.
Cgen (cstage):
- call site: when the callee has a variadic last param,
materialise the tail args into a frame-resident `[N]T` via
localoff, write a 24B slice descriptor (ptr,len,cap), and
splice a synthesised N_IDENT into args[] so the downstream
widen/eval/pop loops see one slice slot. Tagged-element types
route each store through cg_widen_tagged_store. Forwarding
skips gather: the N_SPREAD wrapper is replaced with its inner
slice expression. Empty form writes {nil,0,0}. args[] / widen[]
bump from 16 to 64 to accommodate Hare's mixed-arg printers.
Selfhost mirror:
- lib/ww/parse: `T...` mark on N_PARAM.op.
- cgen: varargseq counter on Cg; scanlocals reserves
@vararg_d_N + @vararg_sl_N per variadic call (seq recorded on
N_CALL.uval so cgcall picks the same names). cgcall does the
same gather/forward and N_IDENT splice. cgfnparams treats
variadic params as 24B slice slots via a synthesised TSLICE
tnode. pushargsrev skips the tagged-widen detection for
variadic params (effective type is []T, not tagged).
- rhstargetname now recognises N_TRUE/N_FALSE/N_RUNELIT and
typed N_INTLIT so the variant-tag lookup finds bool/rune/iN
variants instead of falling through to "first non-str" (which
misassigned tag 0 to bool in tagged unions like formattable).
lib/fmt graduated: print/println/fprint/fprintln/errorln/fatal
take `args: formattable...`. Bare `error` (no -ln) is skipped —
the leaf name collides with strconv's `type error = !(invalid |
overflow)` under the driver's flat namespace.
Tests: 5 new e2e rows (plain gather, zero-arg, tagged element,
forwarding, fmt.println end-to-end). lib/CLAUDE.md workaround
paragraph replaced with the Hare-shape description.
Six fixes across the toolchain, surfaced by lib/lisp porting work.
1. f64 compound assigns (`acc += d`, `-=`, `*=`, `/=`). Both stages
load slot → X1, OP X0 into X1, store back (ADDSD/SUBSD/MULSD/
DIVSD are reg-reg only). Previous MOVSD-overwrite dropped the
OP. Locals and top-level lets.
2. Top-level `[N]u8` arrays + `&arr[i]`. let_emit_size grows a
TY_ARRAY branch so zero-init DATAW lands; cgindex / N_INDEX
store / `&base[i]` all detect a global array base and use
LEAQ name(SB) instead of LEAQ (BP). TK_AMP no longer pre-
evaluates the operand as a value-load — `&base[i]` computes
base + i*esz directly. Unblocks Hare's static-buffer pattern:
strconv.{u64,i64,f64}tos graduate to module-level `*_buf`
arrays and return owned views.
3. Cross-module `pkg.Enum.MEMBER`. Nested N_DOT chains that
don't fold to a known shape now emit `MOVQ <leaf>(SB), AX`
(mirrors the bare-IDENT unresolved fallback), so isolation
probes — and the test 990 cgen-match floor — stay consistent
across stages. strconv exposes `base` as a real `enum i32`;
callers updated. The `main` exemption (linker entry-point
keeps bare name even when not exported) mirrors C-side
collectmods into selfhost cgendecl.
4. Sum-typed parameter ABI. lib/bytes.{index,rindex} take
`(u8 | []u8)` needle; lib/strings.byteindex / rbyteindex take
`(str | rune)` needle (Hare-shaped; the byte-wise misnomer
`index` is dropped). tagged_arg_size cap bumps to 48 (6 int
regs), with a new partial-fit branch on the callee: when an
N-word tagged arg overflows remaining regs, fill what fits and
stitch the rest from positive BP offsets. scanlocals MCASE
handles slice binds (24B) and walks each arm with a saved /
restored seenmark set so two arms naming the same local each
get their own slot — matches cstage's per-arm scope reset.
5. 4-reg tagged-return ABI (AX=tag, DX=word0, CX=word1, R8=word2),
up from 3 regs. Slice-payload variants (`([]T | E)`, slot 32B)
round-trip ptr/len/cap end-to-end. Every receive site updates:
let-init via cgwidentaggedstore, match scrutinee spill, cgindex
tagged-element load (both N_IDENT and fallback bases),
pushargsrev tagged-ident arg (reads word count from slot size),
cgreturn slice variant in the shuffle path.
6. `expr: TaggedAlias` is a widening, not a re-interpret. C cgen +
selfhost cgwidentaggedstore peel an N_CAST whose destination IS
the union — so cgexpr's natural shape (str: AX=ptr, BX=len;
slice: AX=ptr, BX=len, CX=cap) is consumed by the matching
concrete-variant branch instead of being misread as a tagged
AX/DX/CX triple. Inner casts to a concrete variant (`7: i32`)
keep their type for proper tag lookup. `[N]Alias` arrays
resolve element size via slotsize + aliaslookup, and aliaslookup
strips a `pkg.` prefix so cross-module references work.
lib/fmt grows `formattable = (i64 | str | bool | rune)` plus
`printv` / `printlnv` taking an explicit `[]formattable` slice (the
receive side of Hare's `args: formattable...`). Call-site variadic
gather isn't wired — callers either hand-build the slice or compose
strconv.i64tos + strings.concat.
700_e2e: 114 → 123 rows (f64 compound, top-level u8 arrays + `&buf[i]`,
pkg.Enum.MEMBER, sum-typed (str|rune) and (u8|[]u8) params, 4-reg
slice-return ABI, formattable array). 26/26 tests, bootstrap stable
through ww4.
i64tos / u64tos / f64tos return a fresh owned str (caller frees via
os.free) instead of writing into a caller-supplied [N]u8. Adds typed
variants (i32tos / i16tos / i8tos and u32 / u16 / u8) and the missing
base parameter on stoi64 / stou64 + typed parse wrappers.
Base values are exported as plain-i32 `def`s (strconv.DEC,
strconv.HEX_UPPER, ...) rather than a `base` enum: cross-module
`strconv.base.DEC` chains miscompile in the cstage cgen — it emits a
memory load through `base(SB)` rather than inlining the constant.
The Sdef path resolves correctly, so callers say `strconv.DEC` and
both cgens lower to an immediate.
Also renames strings.byteindex / rbyteindex to strings.indexbyte /
rindexbyte, matching bytes.indexbyte and reserving the Hare name
`byteindex` for the future `(str | rune)`-needle shape.
fmt drops printint / printlnint / fprintint — those were stand-ins
for variadic `fmt::println(42)`; with the owned-str graduation the
substitute is one call: `fmt.println(strconv.i64tos(42, strconv.DEC))`.
strerror is sketched in a comment but not shipped — match arms over
the wider `error = !(invalid | overflow)` union still expose a
cstage-vs-wwstage spill divergence.
ascii.digitval/isidstart/isidpart are lexer-private, not Hare-stdlib.
Moved into lib/ww/lex/lex.ww as fn (renamed digitval to hexval since
its sole job is the \\xHH escape decoder).
bytes.copy and fmt.errpos have no Hare counterpart and no external
callers; gone.
