Bend 2.0.37

[Lorenzobattistela]

• A Nat crosses to a JS host as a plain number (PR A Nat crosses to a JS host as a plain number #1506 by
  nicolas-abril). Breaking for JS callers: an effect's .js and a
  caller of an exported def pass and get 5, not 5n. A Nat answer or
  argument that isn't a whole number from 0 to 2^53 stops the run with the
  Nat error, as in C. Calls into exported defs are about 3.5x faster.
• IO.exit(code) ends a program quietly with a status from 0 to 255
  (main cannot set an exit status without writing to stderr, and IO.die codes above 255 wrap (256 exits 0) #1465, PR fix(io): add quiet exit and reject out-of-range status codes #1492 by oxura). A code above 255, in IO.exit or IO.die,
  exits 1 instead of wrapping.
• F32.show takes a plain parameter, so ~F32.show fits List.show
  and Maybe.show (F32.show takes +a, so ~F32.show cannot be passed to List.show or Maybe.show, unlike every other Base show #1511, PR fix(base): use a plain parameter for F32.show #1518 by vicmcorrea). A caller passing it as
  + now wraps it: (x => F32.show(x)).
• bend-lint, a standalone linter with rules written in TS or Bend, in
  tools/bend-lint (PR adds bend-lint tool #1389 by MattCozendey).
• Faster:
  • The CPU hands a slow grow's forks to idle threads, so a wide late fork
    runs 2.6x faster at 14 threads (On the CPU, a call before each fork keeps a fork tree on a few threads: 256 leaves get 3.5x from 16 threads instead of 14x #1475, PR fix(cpu): deal a slow grow's forks to idle threads (#1475) #1479 by viridale).
  • BendTT's parser reads the text's bytes, so --verdict parses twice as
    fast in a quarter of the memory (PR BendTT's parser reads the text's UTF-8 bytes at a position, not a List Char, so it parses twice as fast in a quarter of the memory #1380 by nicolas-abril); safe.ts
    walks each term once (PR safe.ts walks each term once for its uses and skips the out-of-scope pass when nothing is out of scope #1384 by nicolas-abril).
  • A bang over a pair no longer sends every closure to the device (PR
    ty_holds walks a type family's body, so a bang over a pair no longer puts every closure on the device #1336 by chaserelock); a spin is a device call by its C's length in
    characters, and always inline on the host (PR A spin is a call on the device when its C is long, by characters not lines, and inline on the host #1413 by nicolas-abril).
  • A native build frees the compiler's memory before clang runs (PR A native build lets go of the compiler's memory before clang runs, so its peak is the larger of the two, not their sum #1385
    by Iann29).
  • On Linux a window paces at the display's refresh rate, not 60 Hz (PR
    On Linux a window paces at the display's refresh rate, not 60 Hz, as the Mac's display sync does #1379 by igorhasse).
• CLI:
  • bend update fails when the installer download fails (bend update returns exit 0 when the installer download fails (v2.0.36) #1481, PR fix(cli): fail updates when installer download fails #1485
    by vicmcorrea).
  • --checkup reads only the import header, and imports with a trailing
    # comment (CLI: --checkup treats import-looking text in a valid multiline string as another module #1501, CLI: --checkup exits green without checking imports that have trailing comments #1497, PRs fix(cli): checkup reads only the import header #1502 by oxura and fix(cli): --checkup reads imports with a trailing # comment #1517).
  • bend a.bend --verdict b.bend is refused: extra arguments go only to a
    plain run (CLI: --verdict silently ignores extra program/file arguments #1503, PR fix(cli): extra arguments only for a plain run #1516).
  • Inline HTML module scripts are bundled (bend <page>.html -o <dir> exits 0 with a 0-byte JS chunk when the page's .bend import is missing or check-failing (the loader never runs) #1400, PR fix(cli): bundle inline HTML module scripts #1412 by oxura), keep
    their diagnostic positions (PR fix(cli): preserve inline script diagnostic positions #1454 by Osraka), and a bundler failure
    is a formatted error (bend <page>.html -o <dir> prints Bun's raw unhandled-error banner (missing page, or -o pointing at an existing file) #1399, PR fix(cli): format page bundler failures #1406 by oxura).
  • An unreachable hub is a formatted error, not a TypeError (PR A hub that cannot be reached is a formatted error, not a raw TypeError #1428 by
    HamedShams); a native build that fails before clang removes its
    /tmp/bend-* dir (bend f.bend -o <binary> leaks one empty /tmp/bend-XXXXXX directory per failed emission (missing foreign import, or no main to run) #1402, PR fix(cli): a native build that fails before clang removes its /tmp/bend-* dir (#1402) #1405 by Yi-111-a).
  • A ! build finds CUDA at $CUDA_PATH and /opt/cuda (PR A ! build finds CUDA at $CUDA_PATH and /opt/cuda too, so Arch's CUDA is no longer skipped #1373 by
    igorhasse).
• Fixes:
  • Linux audio keeps a partially written chunk until ALSA takes it, and
    stops on a dead device instead of spinning (PR fix(audio): keep Linux partial writes and stop on a dead device #1508 by
    sebastian-griego).
  • F32.hypot keeps lengths past 1.8e19 and below 1e-19 (PR fix(base): retain representable F32.hypot lengths #1515 by
    sebastian-griego).
  • A closed stdout or stderr reader ends a program by SIGPIPE (A program whose stdout reader exits early prints bend: a short write on a standard stream and exits 1 #1467, PR
    A closed stdout or stderr reader ends a program by SIGPIPE, not with an error (#1467) #1470 by viridale); Process.run reads until stdout and stderr close
    (Process.run JS lane times out after the direct child exits with inherited pipes #1343, PR Process.run reads until stdout and stderr close, as Node's and Bun 1.4's spawnSync do #1392 by nicolas-abril); get_env rejects a name with a NUL
    (IO.get_env on Node truncates names at embedded NUL #1449, PR fix(io): get_env rejects a name with an embedded NUL #1450 by Yi-111-a).
  • An erased last argument no longer cuts its call (C backend: a def whose last parameter is erased compiles its parallel let as two sequential calls #1374, PR An erased last argument no longer cuts its call, so a def whose last parameter is erased keeps its fork (#1374) #1377 by
    nuxyel); the effect table is sized to the program's constructor ids
    (Every compiled IO program carries ~1 MiB of zeros: io_eff_rows is baked into .data.rel.ro by clang #1163, PR fix(runtime): size effect table to program constructor IDs #1378 by vicmcorrea); arrays of concrete functions compile
    (An Array of a concrete function type (Array<(U32 -> U32)>) checks and runs on the interpreter but stops both emitters with "an open Array element type" (follow-on to #1130) #1404, PR fix(compiler): support concrete function array elements #1410 by oxura); lay_el takes only datatypes and type
    formers (PR fix(compiler): lay_el accepts datatypes and type formers only #1426 by nicolas-abril); a __proto__ export survives in
    JS (PR fix(compiler): preserve __proto__ JS module exports #1458 by vicmcorrea).
  • Match-refined Data views stay in copyable lets (-o/--verdict leave out a def that copies a hypothesis of computed type after a match refined it ("a λ that uses a variable twice") (2.0.35) #1349, PR Preserve match-refined Data views in copyable lets #1369 by
    oxura); Array-wrapped JS marshalling is stack-safe (JS effect marshaller overflows the host stack when recursion is nested under Array #1346, PR Make Array-wrapped JS marshalling stack-safe #1370 by
    oxura).
  • --verdict builds inlined recursive let arguments at each use (--verdict certifies a different main (kernel 1, bend2 0n): a let passed to a self-call is built at the let, so a convoy captures it (#1168 via let_term) #1326,
    PR fix(verdict): build inlined recursive let arguments at each use #1368 by oxura), keeps Base-free large Nat literals (Without import Base, safe.ts writes a Nat literal above 4096 as the book's own Nat.add(Nat.mul(q, 4096), r), so --verdict passes a book whose certified main is 1n while bend2 runs it to 4097n #1330, PR fix(verdict): preserve Base-free large Nat literals #1337
    by oxura), and parses both rewrite motive binders in its diagnostics
    (Diagnostic bug: safe_diag cannot parse current rewrite syntax and misreports valid recursion #1315, PR fix(diagnostics): parse both rewrite motive binders #1407 by oxura).
  • The formatter keeps module import paths (PR fix(formatter): preserve module import paths #1325) and separated brace
    arguments (PR fix(formatter): preserve separated brace arguments #1505), by vicmcorrea; the linter keeps quoted foreign
    import paths (PR fix(lint): preserve quoted foreign import paths #1422) and module headers (PR fix(lint): respect module headers in declaration guard #1460), by vicmcorrea.
• Docs: README Limitations names backend divergence and the unproven
  translation (README Limitations: note backend divergence and unproven translation #1423, PR README Limitations: backend divergence and unproven translation #1424); the formatter README installs
  bend2-fmt-lsp on PATH (PR docs(formatter): document editor command installation #1486 by Osraka); IO forks vs CPU parallel
  calls (IO.fork computations run their pure work on one core; the guide says "in parallel, on every core" #1375, PR docs: distinguish IO forks from CPU parallel calls #1415 by oxura); BendRT's opening program checks again
  (Documentation bug: The BendRT paper’s opening example fails type checking #1308, PR Make the BendRT opening program check again and rebuild its PDF #1382 by oxura).

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Checks on 16b5db1 (main 0e14aa8 + VERSION/CHANGELOG): repo 54/54, test 1606/1606, ping 56/56, perf 124/124.