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WAFER/CHANGELOG.md
T
Oleksandr Kozachuk 706c73ce2a feat(core): SwiftForth input number conversion, DPL and NH
Punctuation (`,` `.` `+` `/` `:` and an embedded `-`) after the leftmost
digit now forces double-cell conversion, so `12.34`, `1,234`, `12:30:45`
and `2026-08-06` convert as doubles. Only a trailing `.` worked before,
and `1.5` was an "unknown word" error.

The punctuation is a double-cell marker, not a fractional point, so the
scale has to travel separately: DPL carries the digit count right of the
rightmost punctuation character (negative when there was none), which is
what lets `<# #>` place the point back on output. NH carries the high
cell a single-cell conversion drops, so a token that overflows a cell is
still recoverable as a double.

parse_number and parse_double_number duplicated the prefix and sign
handling and could not share a DPL counter, so they collapse into one
parse_numeric_literal that reports which kind it converted.

Verified token-for-token against sf64. One deliberate divergence: WAFER
keeps accepting a sign before a base prefix (`-$FF`), which sf64 rejects.
2026-08-06 19:19:41 +02:00

6.8 KiB

Changelog

All notable changes to WAFER are documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

[0.2.2] - 2026-08-06

Added

  • SwiftForth-style input number conversion. Punctuation (, . + / : and an embedded -) anywhere after the leftmost digit now forces double-cell conversion, so 12.34, 1,234, 12:30:45 and 2026-08-06 all convert as doubles without a custom parser. Previously only a trailing . worked and 1.5 was an "unknown word" error. The punctuation is a double-cell marker, not a fractional point: every spelling of 1234 (1234., 123.4, .1234) yields the same value.
  • DPL ( -- addr ): digits to the right of the rightmost punctuation character in the last converted number, negative when the token carried none. Seeded at -1024 and bumped once per digit, matching sf64. Together with <# #> this is how fixed-point input is scaled.
  • NH ( -- addr ): the high-order cell dropped by a single-cell conversion, so a token that overflows a cell can be recovered as a double (4000000000 NH @ D.).

Verified token-for-token against SwiftForth sf64: DPL values, double promotion and sign handling agree on every probed form. One deliberate divergence — WAFER also accepts a sign before a base prefix (-$FF), which sf64 rejects; the Forth 2012 spelling $-FF works in both. A leading + is punctuation rather than a sign in both engines, so +7 is the double 7 with DPL = 1.

0.2.1 - 2026-08-06

Fixed

  • The search order is now authoritative (Forth 2012 §16.3.3): a word whose wordlist is not in the search order is no longer findable. Previously lookup fell back to the newest entry across all wordlists, making word hiding impossible. Verified against gforth and SwiftForth, and guarded by a cross-engine corpus program.
  • Host words validate their stack arguments. Around 40 host-implemented words (RND-SEED, ACCEPT, RESIZE, ALLOCATE, FREE, SEARCH, SUBSTITUTE, ROLL, M*, UM/MOD, SF@ SF! DF@ DF!, F. FE. FS. F~, 2R@, and friends) performed raw stack-pointer arithmetic with no underflow check — calling them on an empty stack silently corrupted the stack pointer (the compiled-code guards from 0.2.0 do not cover host words). All argument-taking host words now fail with a clean, CATCHable underflow error, enforced by a class-wide regression test.

0.2.0 - 2026-08-06

The usability release: introspection, source files, honest errors, and a safety net under every compiled word.

Added

  • Stack guards in compiled code: under/overflow checks at the stack-pointer choke points of generated WASM. Faults THROW standard codes (-3..-6, -44, -45), are CATCHable, and print standard messages instead of silently corrupting memory. Default on; wafer build output stays unguarded; WAFER_STACK_GUARDS=0|1 overrides.
  • SEE: source-level decompiler. Colon words (including everything in boot.fth) show their captured verbatim source; data words show synthesized definitions with current values (9 VALUE X, DEFER D ( IS DUP )); primitives fall back to a readable IR dump — SEE never dead-ends on a defined word.
  • SEE-IR: post-optimization IR view with resolved callee names and indented control flow — shows what the optimizer actually did.
  • HELP: stack effect + one-line description for every word in a fresh VM (dictionary words and outer-interpreter tokens alike); coverage is enforced by a unit test, so an undocumented new word fails the build. User words echo their leading ( n -- n ) comment.
  • INCLUDE / INCLUDED: nestable source-file loading with cycle detection, depth bound, paths relative to the including file, and per-level SOURCE-ID. The loader is injected (CLI: filesystem; web: defined error), so the core stays IO-free. wafer prog.fth now runs through the same machinery.
  • MARKER extensions: REMEMBER (re-runnable marker), EMPTY and GILD (boot-state rollback and re-baselining). Marker rollback now also restores search order, wordlists, REPLACES substitutions, ABORT" texts, and captured word sources — enabling the REMEMBER + INCLUDE edit-reload loop.
  • WORDS: optional substring filter (WORDS FLOAT), word count, and WORDS ALL — a grouped full view by wordlist plus internal words.
  • Return-stack introspection: .RS, RDEPTH, RP@.
  • Tools: .S honors BASE, F.S, ?, bounds-checked DUMP, real BYE, named ORDER output.
  • CLI REPL: persistent history (XDG state dir, 0600), dictionary-backed tab completion, prefix history search on Up/Down, Ctrl-C clears the line.
  • Web REPL: history persisted to localStorage, User Words palette, BASE indicator in the stack bar.
  • Error reporting: uncaught THROW codes map to standard messages; ABORT" text prints only when uncaught; errors inside included files carry file.fth:line: context; uncaught throws are typed (WaferError::UncaughtThrow) for embedding consumers; compiled words carry WASM name sections, so genuine traps name the faulting word (in CRASHER: wasm trap: out of bounds memory access).
  • SwiftForth correctness lane: the cross-engine program corpus can run against sf64 as an oracle (just compare-correctness), alongside the existing gforth lane and the sf64 performance lane.

Fixed

  • Multi-line command output in the CLI REPL starts on its own line (inline ok echo only for single-line output).
  • .S printed in decimal regardless of BASE.
  • A bare interpreted R> underflowed silently (exposed by the new stack guards; compliance baseline updated).
  • SPACES with a negative count now outputs nothing, per Forth 2012 6.1.2230.

Changed

  • wafer prog.fth reports errors with file:line context and resolves nested INCLUDEs relative to the file.
  • Internal words (_-prefixed) are flagged in the dictionary and hidden from WORDS and completion (WORDS ALL shows them).
  • Dependencies upgraded across the board: wasmtime 43 → 47, wasm-encoder/wasmparser 0.246 → 0.255, plus all semver-compatible updates.

0.1.0 - 2026-08-04

Initial development line (untagged): Forth 2012 core with IR optimizer and WASM codegen via wasm-encoder/wasmtime, ~300 words across Core, Double, Float, String, Search-Order, Exception, and Tools word sets, Forth 2012 compliance suite, CONSOLIDATE whole-program recompilation, wafer build AOT export (WASM / native / JS loader), browser REPL, SHA-1/256/512 words, and cross-engine benchmark lanes against gforth and SwiftForth.