`S name` is the string analogue of `[CHAR] x` and `['] name`: parses the
next whitespace-delimited token, state-smart.
Interpret: leaves ( c-addr u ) pointing into the input buffer.
Compile: appends run-time push of the copied bytes (identical code
to writing S" name" inline).
One line in boot.fth, leverages the existing PARSE-NAME + SLITERAL.
Zero runtime overhead inside : definitions.
Major compliance push bringing WAFER from 3 to 10 passing Forth 2012
compliance test suites (Core, Core Extensions, Core Plus, Double,
Exception, Facility, Locals, Memory, Search Order, String).
Compiler/runtime fixes:
- DEFER: host function via pending_define, works inside colon defs
- COMPILE,: handle_pending_compile in execute_word for [...] sequences
- MARKER: full save/restore with pending_marker_restore mechanism
- IMMEDIATE: changed from XOR toggle to OR set per Forth 2012 spec
- ABORT": throw -2 via THROW, no message display when caught
- M*/: symmetric division to match WAFER's / behavior
- pending_define: single i32 flag → Vec<i32> queue for multi-action words
- Optimizer: prevent inlining words containing EXIT or ForthLocal ops
- +LOOP: corrected boundary check formula with AND step comparison
- REPEAT: accept bare BEGIN (unstructured IF...BEGIN...REPEAT)
- Auto-close unclosed IFs at ; for unstructured control flow
- _create_part_: use reserve_fn_index to preserve dictionary.latest()
Memory layout:
- Separate PICT_BUF and WORD_BUF regions to prevent PAD overlap
- Updated DEPTH hardcoded DATA_STACK_TOP in boot.fth
New word sets:
- [IF]/[ELSE]/[THEN]/[DEFINED]/[UNDEFINED]: conditional compilation
- UNESCAPE/SUBSTITUTE/REPLACES: string substitution (host functions)
- Locals {: syntax: parser, ForthLocalGet/Set IR ops, WASM local codegen
- ENVIRONMENT? support for #LOCALS (returns 16)
- N>R/NR>/SYNONYM: programming-tools extensions
- Search Order: ONLY, ALSO, PREVIOUS, DEFINITIONS, FORTH,
FORTH-WORDLIST, GET-ORDER, SET-ORDER, GET-CURRENT, SET-CURRENT,
WORDLIST, SEARCH-WORDLIST with full multi-wordlist dictionary support
via Arc<Mutex> shared state for immediate effect from compiled code
Remaining: 1 cascade error in Programming-Tools from CS-PICK/CS-ROLL
(unstructured control-flow stack manipulation, requires flat IR).
- DU< had same comparison order bug as D< (comparing d2-hi < d1-hi
instead of d1-hi < d2-hi). Fixed with SWAP U<.
- 2VARIABLE and 2CONSTANT were handled as special tokens but not
registered in the dictionary, so they couldn't be called from
compiled code (e.g., : CD4 2VARIABLE ;). Added pending codes 9/10.
- D< used D- D0< which overflows for extreme signed doubles.
Replaced with high-cell comparison + unsigned low-cell comparison.
- COMPARE had inverted sign for length difference (u2-u1 vs u1-u2).
- Added -TRAILING (removed during Phase 6 refactoring, never re-added).
Six fixes for compliance test regressions introduced in Phases 7-8:
- LEAVE + +LOOP with step=0 caused infinite loop: the XOR termination
check yields 0 when index=limit and step=0. Added SYSVAR_LEAVE_FLAG
mechanism — LEAVE sets flag, +LOOP checks it, all loops clear on exit.
- DEPTH was off-by-one: `5440 SP@ -` pushed the literal before SP@
read the stack pointer, making SP@ see one extra cell. Reordered to
`SP@ 5440 SWAP -` so SP@ reads dsp before any literal push.
- */ and */MOD used FM/MOD (floored) but WAFER's / uses WASM i32.div_s
(symmetric). Changed to SM/REM for consistency.
- EVALUATE didn't sync input buffer to WASM memory, breaking SOURCE
and >IN manipulation inside evaluated strings. Added input-only sync
(without touching STATE/BASE) and >IN readback after each token.
- WORD didn't skip leading spaces when delimiter != space, causing
GN' and GS3 tests to read whitespace instead of content.
- Added ACCEPT stub returning 0 for non-interactive mode.
- Added bounds check in refresh_user_here to reject corrupted
SYSVAR_HERE values beyond WASM memory size.
Core and Facility compliance suites now pass. Other suites have
pre-existing regressions from Phases 1-8 still under investigation.
Move memory allocation words to boot.fth:
- ALLOT: `: ALLOT HERE + 12 ! ;`
- , (comma): `: , HERE ! 1 CELLS ALLOT ;`
- C, : `: C, HERE C! 1 ALLOT ;`
- ALIGN: `: ALIGN HERE ALIGNED 12 ! ;`
- FALIGN, SFALIGN, DFALIGN: float-aligned variants
These write directly to WASM memory[SYSVAR_HERE]. The Rust side picks up
Forth-side HERE changes via refresh_user_here() which now reads both
here_cell (for Rust host functions) and memory[12] (for Forth words),
taking the maximum to ensure no allocation is lost.
Removed 222 lines of Rust. All 426 tests pass.
DEFER! and DEFER@ are trivially `: DEFER! >BODY ! ;` and `: DEFER@ >BODY @ ;`.
COMPARE uses a byte-by-byte loop with early exit.
Removed 148 lines of Rust. All 426 tests pass.
Move to boot.fth: TYPE, SPACES, <#, HOLD, HOLDS, SIGN, #, #S, #>,
., U., .R, U.R, D., D.R. The Forth . now uses pictured numeric output
(standard Forth approach) instead of a Rust formatting closure.
Add M*, UM*, UM/MOD host functions to the WASM runner so that the
Forth # word (which calls UM/MOD) works in standalone mode.
Removed 660 lines of Rust closures + 5 dead helper functions.
All 426 tests pass.
HERE is now defined in boot.fth as `: HERE 12 @ ;` (reads SYSVAR_HERE
from WASM linear memory). The Rust side syncs user_here to memory[12]:
- At the start of each evaluate() call (sync_here_to_wasm)
- In each host function that modifies HERE (ALLOT, comma, C-comma, ALIGN)
This avoids per-token sync overhead — only 2 sync points per evaluate()
call plus host-function writes. Removed the HERE host function closure
(~30 lines). All 426 tests pass.
Now that the optimizer TailCall/inline bug is fixed, SM/REM, FM/MOD,
*/, and */MOD can be defined in Forth using M* and UM/MOD as primitives.
SM/REM uses DABS (which calls DNEGATE → D+) inside conditional branches
with return-stack items — exactly the pattern that triggered the bug.
Removed ~200 lines of Rust closures. All 426 tests pass.
Add 14 double-cell words to boot.fth: D+, D-, DNEGATE, DABS, D0=, D0<,
D=, D<, D2*, D2/, DMAX, DMIN, M+, DU<.
Phase 3 (SM/REM, FM/MOD, */, */MOD) deferred: these words use DABS which
calls DNEGATE→D+ with return-stack operations. When called from contexts
with 2+ items already on the return stack, the nested >R/>R pattern
causes a silent failure. Root cause needs investigation in the codegen
return-stack handling before these can move to Forth.
All 425 tests pass.
Move to boot.fth: D+, D-, DNEGATE, DABS, D0=, D0<, D=, D<, D2*, D2/,
DMAX, DMIN, M+, DU<.
D+ uses proper carry detection via unsigned comparison after low-cell
addition. All other double-cell words build on D+ and standard Forth
stack operations.
Removed 544 lines of Rust closures. Cumulative: ~1,091 Rust lines removed
across Phases 1-2, replaced by ~80 lines of Forth. All 425 tests pass.
Create boot.fth loaded at startup after IR primitives are compiled.
Forth-compiled WASM with direct calls outperforms host function dispatch
(no call_indirect overhead, Cranelift can inline across word boundaries).
Words moved to Forth: 2OVER, 2ROT, WITHIN, 2@, 2!, FILL, CMOVE, CMOVE>,
MOVE, ERASE, BLANK, /STRING, -TRAILING.
Removed 547 lines of Rust closures, replaced by 48 lines of Forth.
All 425 tests pass.
ok