package js_of_ocaml

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Compiler from OCaml bytecode to JavaScript


Dune Dependency





5.7.1 (2024-03-05) - Lille


  • Compiler: only flush the necessary env for closures (#1568)

  • Library: dialog element support

Bug fixes

  • Compiler: fix --enable=vardecl

  • Compiler: fix parallel renaming (bug introduced in #1567)

  • Lib: fix paragraph construction and coercion

  • Runtime: reduce memory leak with channels (#1581)

5.7.0 (2024-02-16) - Lille


  • Mics: fix support for OCaml 5.2

  • Compiler: no longer rely on IIFE for scoping variable inside loops

  • Compiler: avoid parsing bytecode sections twice, jsoo counter part of ocaml#12599

  • Lib: add ellipse to canvasRenderingContext2D (@FayCarsons, #1555)

Bug fixes

  • Compiler: fix global dead code elimination in a toplevel context

  • Compiler: fix exit-loop-early optim in presence of closure (#1561)

  • Compiler: remove quadratic behavior in (#1531, #1567)

5.6.0 (2024-01-02) - Lille


  • Compiler: try to preserve clorures ordering between ml and js

  • Compiler: js-parser accept for await

Bug fixes

  • Compiler: js-parser now accept all the line terminators defined in the spec

  • Compiler: js-parser: fix support for LHS assignment target

  • Compiler: js-parser: fix parser of default export

  • Compiler: js-parser: allow 'as' as ident

  • Compiler: js-parser: fix for-in rewriting

  • Compiler: js-parser: fix yield pretty print

  • Compiler: js-parser: fix async arrow function

  • Compiler: js-parser: fix class printing

  • Compiler: js-parser: fix #privateName

5.5.2 (2023-12-01) - Lille


  • Compiler: global dead code elimination (Micah Cantor, #1503)

  • Compiler: change control-flow compilation strategy (#1496)

  • Compiler: loop no longer absorb the whole continuation

  • Compiler: Dead code elimination of unused references (#2076)

  • Compiler: reduce memory consumption (#1516)

  • Compiler: support for import and export construct in the js parser/printer

  • Lib: add download attribute to anchor element

  • Misc: switch CI to OCaml 5.1

  • Misc: preliminary support for OCaml 5.2

  • Misc: support for OCaml 5.1.1

Bug fixes

  • Runtime: fix Dom_html.onIE (#1493)

  • Runtime: add conversion functions + strict equality for compatibility with Wasm_of_ocaml (#1492)

  • Runtime: Dynlink should be able to find symbols in jsoo_runtime #1517

  • Runtime: fix Unix.lstat, Unix.LargeFile.lstat (#1519)

  • Compiler: fix global flow analysis (#1494)

  • Compiler: fix js parser/printer wrt async functions (#1515)

  • Compiler: fix free variables pass wrt parameters' default value (#1521)

  • Compiler: fix free variables for classes

  • Compiler: fix internal invariant (continuation)

  • Compiler: fix variable renaming for let, const and classes

  • Lib: Url.Current.set_fragment need not any urlencode (#1497)

5.4.0 (2023-07-06) - Lille

Bug fixes

  • Runtime: Fix recursive modules on ocaml < 4.13 (#1485)

  • Runtime: fix hashing of NaN (#1475)

  • Runtime: float rounding should resolve tie away from zero (#1475)

  • Runtime: fix Gc.stat, Gc.quick_stat, Gc.get (#1475)

  • Compiler: fix some miscompilation, probably introduced in jsoo 5.0.0, revealed by OCaml 5.0

5.3.0 (2023-06-21) - Lille


  • Misc: Bump magic number for ocaml 5.1

  • Misc: changes to stay compatible with the next version of ppx_expect

  • Runtime: support conversion of Uint8ClampedArray typed arrays to bigarrays (#1472)

Bug fixes

  • Compiler: fix location for parsing errors when last token is a virtual semicolon

  • Compiler: fix variable renaming with nested const/let decl with identical names

  • Compiler: fix variable renaming inside js method

  • Compiler: consise body should allow any expression but object literals

  • Compiler: preserve [new] without arguments [new C] (vs [new C()]

  • Compiler: remove invalid rewriting of js (#1471, #1469)

  • Runtime: fix int32 values returned from bigarrays when wrapping Uint32Array objects (#1472)

5.2.0 (2023-04-28) - Lille


  • Compiler: jsoo link archive with -a (#1428)

Bug fixes

  • Compiler: put custom header at the top of the output file (fix #1441)

  • Compiler (js parser): fix parsing of js labels (fix #1440)

  • Compiler: fix simplification of js with let and const

  • Compiler: reduce memory consumption when parsing js

  • Compiler: parsing js can return a list of token, the list was sometime incorrect

  • Sourcemap: stop producing sourcemaps mappings with negative lines or columns

  • Runtime: fix marshalling with sharing and string (use-js-string)

5.1.1 (2023-03-15) - Lille

Bug fixes

  • Compiler: fix jsoo link in presence of --disable use-js-string (#1430)

5.1.0 (2023-03-07) - Otari


  • Lib: Added support for KeyboardEvent.getModifierState

  • Misc: bump min ocaml version to 4.08

  • Misc: remove some old runtime files to support some external libs

  • Misc: switch to dune 3.7

  • Effects: partial CPS transformation, resulting in much better performances, lower compilation time and smaller generated code

  • Compiler: separate compilation can now drops unused units when linking (similar to ocamlc). (#1378)

  • Compiler: specialize string to js-string conversion for all valid utf8 strings (previously just ascii)

  • Compiler: JavaScript files generated by js_of_ocaml are now UTF-8 encoded.

  • Compiler: use identifier for object literals when possible

  • Compiler: Cache function arity (the length prop of a function is slow with v8)

  • Compiler: The js lexer is now utf8 aware, recognize and emit utf8 ident

  • Compiler: Update the js lexer with new number literal syntax

  • Compiler: update js parser to support most es6 feature (#1391)

  • Compiler: stop parsing the builtin js runtime if not necessary

  • Compiler: improve js pretty printer (#1405)

  • Compiler: improve debug location and speedup compilation (#1407)

  • Compiler: improve analysis for more direct call (#1397)

  • Compiler: change memory representation of OCaml strings to use js ones.

  • Toplevel: Enable separate compilation of toplevels

  • Runtime: js backtrace recording controled by OCAMLRUNPARAM

  • Runtime: support for zstd decompression of marshalled data (ocaml.5.1) (#12006)

  • Runtime: stub out custom runtime events symbols for OCaml 5.1 (#1414)

Bug fixes

  • Effects: fix Js.export and Js.export_all to work with functions (#1417,#1377)

  • Sourcemap: fix incorrect sourcemap with separate compilation

  • Compiler: fix control flow analysis; some annotions were wrong in the runtime

  • Compiler: js backtrace recording respected in the js runtime and when using effects

  • Compiler: no longer fail on invalid source file (when the file is a directory)

  • Runtime: fix the compilation of some mutually recursive functions

5.0.1 (2022-12-20) - Lille


Bug fixes

Runtime: fix caml_read_file_content

5.0.0 (2022-12-20) - Lille


  • Compiler: add support for effect handlers (--enable=effects)

  • Compiler: small refactoring in code generation

  • Compiler: check build info compatibility when linking js file.

  • Compiler: rewrite control flow compilation logic

  • Misc: fix and update benchmarks

  • Misc: upgrade CI

  • Toplevel: recover more names when generating code during toplevel evaluation

  • Runtime: wrapping exception or not is now controled in the runtime.

Bug fixes

  • Runime: Gc.finalise_last should not be eliminated

  • Tyxml: reactive dom needed a fix after #1268 (#1353)

  • Toplevel: Make sure the toplevel uses the correct memory representaion for strings

  • Compiler: fix minifier, missing constraint on try-catch blocks.

  • Compiler: Miscompilation of code involving references and exceptions (#1354, #1356)

4.1.0 (2022-11-15) - Lille


  • Compiler: initial support for OCaml 5 (#1265,#1303)

  • Compiler: bump magic number to match the 5.0.0~alpha0 release (#1288)

  • Compiler: complain when runtime and compiler built-in primitives disagree (#1312)

  • Compiler: more efficient implementation of Js_traverse.freevar

  • Compiler: more efficient implementation of Js_traverse.rename_variable

  • Compiler: --linkall now export all compilation units in addition to primitives (#1324)

  • Compiler: improve --dynlink, one no longer need to pass --toplevel to use Dynlink (#1324)

  • Compiler: toplevel runtime files "+toplevel.js" and "+dynlink.js" are added automatically (#1324)

  • Misc: switch to cmdliner.1.1.0

  • Misc: remove old binaries jsoo_link, jsoo_fs

  • Misc: remove uchar dep

  • Misc: use 4.14 in the CI

  • Misc: switch to dune 3

  • Lib: add missing options for Intl.DateTimeFormat

  • Lib: add missing options for Intl.NumberFormat

  • Lib: wheel event binding

  • Lib: add normalize in js_string (ES6)

  • Lib: more complete transition event bindings

  • Lib: remove support for old browser-specific transition events

  • Runtime: Implement weak semantic for weak and ephemeron (#1268)

  • Runtime: Implement Gc.finalise_last

  • Runtime: Implement buffer for in_channels

  • Runtime: add support for unix_opendir, unix_readdir, unix_closedir, win_findfirst, win_findnext, win_findclose

  • Runtime: Dont use require when target-env is browser

  • Runtime: Implements Parsing.set_trace (#1308)

  • Runtime: ocaml string are represented as javascript ones.

  • Test: track external used in the stdlib and unix

Bug fixes

  • Compiler: fix quadratic behavior of dominance frontier (fix #1300)

  • Compiler: fix rewriter bug in share_constant (fix #1247)

  • Compiler: fix miscompilation of mutually recursive functions in loop (#1321)

  • Compiler: fix bug while minifying/renaming try-catch blocks

  • Compiler: no dead code elimination for caml_js_get

  • Runtime: fix ocamlyacc parse engine (#1307)

  • Runtime: fix Out_channel.is_buffered, set_buffered

  • Runtime: fix format wrt alternative

  • Runtime: fix

  • Runtime: sync channel seek / pos with the native runtime

  • Misc: fix installation with dune 3 without opam

  • Node: Only write small chunks to stdout/stderr so they flush

  • Deriving: fix for nested polymorphic variants

4.0.0 (2021-01-24) - Lille


  • Compiler: add --target-env flag, for JS runtime specific compilation targets (#1160).

  • Compiler: static evaluation of backend_type (#1166)

  • Compiler: speedup emitting js files (#1174)

  • Compiler: simplify (a | 0) >>> 0 into (a >>> 0) (#1177)

  • Compiler: improve static evaluation of cond (#1178)

  • Compiler: be more consistent dealing with js vs ocaml strings (#984)

  • Compiler: Compiler: add BigInt to provided symbols (fix #1168) (#1191)

  • Compiler: use globalThis, drop joo_global_object #1193

  • Compiler: new -Werror flag to turn wanrings into errors (#1222)

  • Compiler: make the inlining less agressive, reduce size, improve pref (#1220)

  • Compiler: rename internal library js_of_ocaml-compiler.runtime to js_of_ocaml-compiler.runtime-files

  • Lib: new runtime library to improve compatibility with Brr and gen_js_api

  • Lib: add messageEvent to Dom_html (#1164)

  • Lib: add PerformanceObserver API (#1164)

  • Lib: add CSSStyleDeclaration.{setProperty, getPropertyValue, getPropertyPriority, removeProperty} (#1170)

  • Lib: make window.{inner,outer}{Width,Height} non-optional

  • Lib: introduce Js_of_ocaml.Js_error module, deprecate Js_of_ocaml.Js.Error exception.

  • Lib: add deprecation warning for deprecated code

  • PPX: json can now be derived for mutable records (#1184)

  • Runtime: use crypto.getRandomValues when available (#1209)

  • Misc: move js_of_ocaml-ocamlbuild out to its own repo

  • Misc: add support for OCaml 4.14 (#1173)

Bug fixes

  • Compiler: fix sourcemap warning for empty cma (#1169)

  • Compiler: Strengthen bound checks. (#1172)

  • Compiler: fix --wrap-with-fun under node (#653, #1171)

  • Compiler: fix parsing of annotaions in js stubs (#1212, fix #1213)

  • Ppx: allow apostrophe in lident (fix #1183) (#1192)

  • Runtime: fix float parsing in hexadecimal form

  • Runtime: fix implementation of caml_js_instanceof

  • Graphics: fix mouse_{x,y} (#1206)

3.11.0 (2021-10-06) - Lille


  • Compiler: setting tc_depth to 0 remove direct call from the tc optimization.

  • Lib: add hidden, onfullscreenchange and onwebkitfullscreenchange to document

  • Runtime: fixes for Windows, all tests pass

  • Runtime: make all windows drive available on nodejs.

  • Runtime: add support for Sys.mkdir and Sys.rmdir

  • Runtime: make stdin work on nodejs

  • Runtime: add support for Unix(stat,lstat,mkdir,rmdir,symlink,readlink,unlink,getuid) on nodejs.

  • Runtime: add caml_raise_with_args

Bug fixes

  • Compiler: fix toplevel generation (#1129, #1130, #1131)

  • Compiler: fix predefined exn id with separate compilation

  • Compiler: js stubs without 'Provides' should still allow 'Require'

  • Runtime: fix handling of uncaugh exceptions

  • Runtime: fix error handling of Sys.readdir

  • Dune: make git version lookup more resilient

3.10.0 (2021-08-30) - Lille


  • Compiler: add support for OCaml 4.13

  • Compiler: new tool to check for missing primitives

  • Compiler: drop support for OCaml 4.03 and bellow

  • Lib: add offsetX and offsetY to Dom_html.mouseEvent

  • Lib: add innerText property for Dom_html

  • Runtime: add dummy implementation for many dummy primitives

  • Runtime: add runtime for new float operation in 4.13 #1113 (by pmwhite)


  • manual/ fix compilation error

3.9.1 (2021-02-17) - Lille


  • Runtime: add missing primitives for OCaml 4.12

Bug fixes

  • Compiler: fix handling of offsetclosure with 4.12

  • Compiler: fix ocaml_version parsing to support tilde

3.9.0 (2021-02-15) - Lille


  • Lib: add clipboardEvent to Dom_html and update appropriate function signatures

  • Lib: add submitEvent to Dom_html and update appropriate function signatures

  • Compiler: complete support for OCaml 4.12

  • Lib: expose API to attached and retrieve js errors to/from ocaml exceptions

  • Lib: intersection observer API fixes

Bug fixes

  • Compiler: fix a segmentation fault when flat-float-array mode is disabled.

3.8.0 (2020-10-21) - London


  • compiler, ppx_js, ppx_deriving_json: port PPX's to ppxlib (#1041)

3.7.1 (2020-09-29) - London


  • lib: Add Navigator.{vendor,maxTouchPoints} (#1062)

  • lib: adds the intersection observer API (#1063)

Bug fixes

  • compiler: revert of "Eliminate allocation of dummy function #1013"

  • compiler: fix for #1051 (#1052), Ensure the overflow warning is always displayed

  • runtime: add missing primitives for 4.11

  • lib: Fix resize-observer (#1058)

3.7.0 (2020-08-05) - Lille


  • Runtime: allow one to override xmlHttpRequest.create (#1002)

  • Runtime: Change the semantic of MlBytes.toString, introduce MlBytes.toUtf16

  • Compiler: initial support for OCaml 4.11

  • Compiler: initial support for OCaml 4.12

  • Compiler: improve the javascript parser by relying on menhir incremental api.

  • Compiler: Eliminate allocation of dummy function #1013

Bug fixes

  • Compiler: fix code generation for recursive function under for-loops (#1009)

  • Compiler: the jsoo compiler compiled to javascript was not behaving correctly when parsing constant in the from the bytecode

  • Compiler: make sure inline doesn't loop indefinitly (#1043)

  • Compiler: fix bug generating invalid javascript for if-then construct (#1046)

  • Compiler: do not use polymorphic comparison when joining float values (#1048)

  • Lib: Rename msg to message in Worker (#1037)

  • Lib: fix graphics_js when build with separate compilation (#1029)

3.6.0 (2020-04-26) - Lille


  • Compiler: change compilation scheme for branches (#948)

  • Compiler: Introduce sub-command: link, build-runtime, build-fs (#987)

  • Compiler: embed javascript runtime in the compiler (#978)

  • Compiler: refactor javascript lexer/parser, add tests (#986)

  • Runtime: clean runtime for string vs bytes

  • Runtime: remove many old polyfill

  • Runtime: add unix_isatty

  • Runtime: optimize caml_call_gen (#996)

  • Runtime: change representation of int64 (#905)

  • Runtime: improve node.js backend for Sys.command (#979)

  • Runtime: add javascript runtime for Str (#998)

  • Lib: add closest method to element (#930)

  • Lib: add several methods and functions to Typed_array (#970)

  • Ppx: ppx_js behave better with merlin (#933)

  • Misc: Cleanup Meta files (e.g. js_of_ocaml.tyxml is no longer valid library name)

  • Misc: switch to ocamlformat.0.14

Bug fixes

  • Compiler: fix vardecl optim (#946)

  • Compiler: restore optimization when generating if statements

  • Compiler: fix javascript parser in the presence of line directives (#980)

  • Runtime: Catch nodejs errors and re-raise them as Sys_error

  • Runtime: fix caml_parse_sign_and_base and unsigned syntax

  • Runtime: fix caml_js_wrap_meth_callback_strict (#996)

  • Runtime: fix over-application of javascript callback (#996)

  • Runtime: fix partial-application of javascript callback (#996)

  • Runtime: fic caml_js_wrap_meth_callback_unsafe (#996)

  • Lib: Fix the type of blur and focus event to be focusEvent (#929)

3.5.2 (2019-12-14) - Hong Kong


  • Misc: support for ocaml 4.10

  • Misc: ppx_deriving_json uses ppxlib >= 0.9

Bug fixes

  • Runtime: fix pseudo fs initialization (#931)

3.5.1 (2019-11-16) - Hong Kong


Bug fixes

  • Runtime: fix poly compare with null and undefined (#920)

  • Lib: Deriving Json does not export an [import] unit

  • Dynlink/toplevel: export all units when no export file is specified (#921)

  • Ppx: ppx_deriving_json should allow [%to_json: t] syntax

3.5.0 (2019-11-10) - Hong Kong


  • Compiler: Improve testing of the compiler (Ty Overby)

  • Compiler: Add several macros for making the runtime easier to maintain (#771) (Ty Overby)

  • Compiler: Allow to emit one javascript per compilation unit (#783)

  • Compiler: refactoring (#781, #782, #787, #795, #802)

  • Compiler: more source map location for the javascript runtime (#795)

  • Compiler: tune variable naming (#838)

  • Compiler: Work around num lib incompatibility

  • Compiler: escape '</' in strings (#899)

  • Compiler: speedup toplevel creation

  • Runtime: support sharing when marshaling (#814)

  • Runtime: add caml_obj_with_tag

  • Runtime: support marshaling custom block

  • Runtime: complete rewrite of bigarray

  • Runtime: complete num implementation

  • Runtime: add caml_ba_hash

  • Runtime: rewrite polymorphic compare

  • Ppx: switch ppx rewriter to the OCaml 4.08 ast

  • Misc: Improve CI speed

  • Misc: remove ppx_deriving dependency

  • Misc: remove cppo dependency

  • Misc: remove ppx_tools_versioned dependency in ppx_deriving_json

  • Misc: support for ocaml 4.09

  • Misc: switch to ocamlformat.0.12

  • Misc: many more tests

  • Misc: new jsoo_fs tool to embed files in a jsoo pseudo fs.

  • Lib: Use expect tests

  • Lib: Add support for 'addEventListener' with options (#807)

  • Lib: Change api of [Lwt_js_events.async] (#862)

  • Lib: Change api of responseText in xmlhttprequest (#863)

  • Lib: add resizeObserver bindings

  • Lib: Added support for custom events (#877)

  • Lib: Added support for focus events (#885)

  • Lib: Added passive option support for Lwt_js_events module

  • Lib: Added bindings for pointer events (#894)

Bug fixes

  • Compiler: don't generate source if no-source-map passed (#780)

  • Compiler: Fix compilation of [Array.set] to return [unit]/0 (#792)

  • Compiler: Fix assertion failure (#828)

  • Compiler: Fix compilation of exception handlers (#830)

  • Compiler: Fix static evaluation of caml_equal (#906)

  • Misc: Fix install on windows (#794)

  • Lib: Fix Dom_svg.createForeignObject (#756)

  • Runtime: Fix caml_obj_tag, causing miscompilation with lazy value (#772)

  • Runtime: Fix caml_ml_seek_out, caml_ml_pos_out (#779) (Shachar Itzhaky)

  • Runtime: caml_parse_sign_and_base to support unsigned syntax (#791) (Shachar Itzhaky)

  • Runtime: fix encoding when printing to stdout (#800)

  • Runtime: Handle browserfs in fs_node detection logic (#831)

  • Runtime: fix Obj.tag (#832)

  • Runtime: fix marshalling of custom blocks (#861)

  • Runtime: fix frexp

  • Runtime: fix float printing with "%f" and large floats

3.4.0 (2019-04-17) - Hong Kong


  • Compiler: Support reproducible builds by using BUILD_PATH_PREFIX_MAP

  • Compiler: Remove support for ocaml < 4.02.3

  • Compiler: use paths from debug info when looking to looking cmis to embed

  • Compiler: refactoring, renaming

  • Compiler: make float literals look like float (#767)

  • Misc: use ocamlformat

  • Misc: dunify the build of the toplevel

  • Misc: support for OCaml 4.08

  • Lib: wrap js_of_ocaml-lwt, js_of_ocaml-tyxml, js_of_ocaml-toplevel, js_of_ocaml-compiler

  • Runtime: don't use deprecated [new Buffer] on nodejs (#726)

Bug fixes

  • Compiler: fix compilation of empty cma

  • Compiler: fix js parser with keyword as ident

  • Compiler, Runtime: make --setenv work with Sys.getenv_opt

  • Compiler: fix miscompilation of Obj.is_int with a match expression

  • Compiler: fix quadratic behaviour in

  • Compiler: prevent addition with a positively-signed number from being coalesced… (#764)

  • Compiler: Fix: static eval of String.get (#770)

  • Runtime: make obj_dup work on string/bytes

  • Runtime: fix bad hash function on int64

  • Runtime: avoid redundant conversion to string in fs_fake.js

3.3.0 (2018-11-26) - Hong Kong


  • Toplevel: [--toplevel] is now taken account when compilig cmo and cma.

  • Lib: make [Js.Unsafe.any] be [ Js.t]

  • Lib: Improve generation of dummy stubs (#700)

  • Lib: Deprecate non namespaced module access

  • Lib: Upgrade to Tyxml 4.3.0

  • Misc: switch to dune

  • Misc: remove camlp4 support

Bug fixes

  • Toplevel: Fix dynlink of precompiled javascript files.

  • Lib: Fix encoding in Sys.set_channel_flusher (fix #686)

  • Runtime: fix the type of dataTransfer##.types

  • Runtime: add dummy implementation for caml_restore_raw_backtrace

3.2.1 (2018-07-26) - Bari

Bug fixes

  • Misc: Fix the dependencies of the Lwt logger

  • Runtime: fix semantic of bigstring_destroy_stub

3.2.0 (2018-06-10) - Bergen


  • Runime: improve stacktraces.

  • Ppx: ppx uses the OCaml 4.06 ast.

  • Misc: support for OCaml 4.07

  • Misc: start leveraging safe-string.

  • Lib: add support for Internationalization API.

  • Lib: Added media events support.

Bug fixes

  • Runtime: int_of_string accepts leading '+'

  • Runtime: fix polymorphic & hash compare on custom non-ocaml values.

  • Runtime: fix string encoding when writing to channels.

  • Runtime: improve mode js detection wrt filesystem.

3.1.0 (2018-02-15) - Hong Kong


  • Lib: add missing File.blob constructor (fix #630)

  • Runtime: hash support for custom blocks

  • Runtime: weak.js loaded by default

  • Compiler: compile an OCaml program into a named javascript function (fix #599)

  • Misc: move ppx_deriving_json in its own opam package (Rudi Grinberg)

  • Compiler: static eval of float negation

  • Compiler: improve constant sharing.

  • Ppx: add support for writeonly_prop and optdef_prop in object literal.

Bug fixes

  • Compiler: fix code generation of unary ops (missing space).

  • Compiler: fix static eval of conditions (fix #616)

  • Compiler: fix code generation for OCaml GPR#1568

  • Runtime: fix bug found using the closure compiler (#644)

3.0.2 (2017-12-01) - Strasbourg


  • Runtime: support for latest core_kernel

Bug fixes

  • Runtime: fix sys_chdir

  • Runtime: fix fs support on windows

  • Ppx: fix ppx_deriving_json for ocaml 4.05

3.0.1 (2017-11-04) - London


  • Lib: add Jstable.remove (Cedric Cellier)

  • Build: use recent version of jbuilder (># 1.0+beta12)

Bug fixes

  • Runtime: fix Sys.file_exists for the in-memory filesystem.

  • Runtime: implement missing primitives: caml_nativeint_bswap, caml_floatarray_*, caml_ba_change_layout

  • Runtime: few other bugfixes.

  • Compiler: fix compat with OCaml 4.06

3.0.0 (2017-06-23) - Hong Kong


  • Misc: switch to ppx instead of camlp4

  • Misc: always install deriving_json

  • Misc: remove support for async_kernel, bin_prot

  • Misc: remove support for ppx_driver

  • Misc: split js_of_ocaml in multiple packages

  • Misc: switch to jbuilder

  • Misc: new pseudo filesystem support with better node support

  • Compiler: sourcemap support is now optional

  • Compiler: no more strong dep on yojson, b64, menhir, ocamllex

  • Compiler: improve separate compilation workflow

  • Runtime: add support for weakdef

  • Syntaxes: add expect tests

  • Syntaxes: switch to ocaml-migrate-parsetree and ppx_tools_versioned

  • Lib: Add primitives in [Js.Unsafe]

  • Lib: remove keycode module, replaced by Dom_html.Keyboard_code

  • Lib: XmlHttpRequest, API change for perform functions.

Bug fixes

  • Runtime: fix many stubs

  • Lib: fix many signatures

  • Compiler: fix performance of compilation passes (simpl,clean)

  • Compiler: fix compat with OCaml 4.06

  • Toplevel: flush channels after execution.

  • Toplevel: fix toplevel generation when using -export-unit

2.8.4 (2016-12-21)


  • Compiler: new jsoo_link binary to link multiple javascript files together and merging sourcemaps.

  • Toplevel: improve generation of toplevels, one can now pass a an export file containing units to export. (see jsoo_listunits)

  • Lib: Provide a Js_of_ocaml (namespace) module to ease transition with future version of js_of_ocaml

Bug fixes

  • Compiler: fix separate compilation when facing empty unit inside a library

  • Runtime: fix many javascript stubs

  • Syntac: fix ppx deriving json

2.8.3 (2016-11-04)


  • Runtime: complete support for 4.04

Bug fixes

  • Compiler: fix order of javascript files

  • Compiler: fix Javascript lexer (newline inside strings)

  • Compiler: fix bug in closure generation

  • Compiler: fix regression in closure generation (introduced in 2.8) (#531)

  • Compiler: fix code generation when static evaluation is disabled

2.8.2 (2016-09-10)


  • Lib: add Dom_html.Keyboard_code & Dom_html.Keyboard_key (Corwin de Boor)

  • Misc: update lib and runtime to work better with non browser environment

  • Misc: initial support for 4.04

Bug fixes

  • Compiler: fix js output for x - -1

  • Compiler: fix parsing of annotations in the runtime

  • Compiler: fix javascript minifier

  • Compiler: various fixes for separate compilation.

2.8.1 (2016-07-01)


  • Compiler: reduce memory usage for shortvar

  • Lib: Add optional prefix arg to

  • Ppx: add ppx_driver compatibility

Bug fixes

  • Lib: fix Js.object_keys, Js.export

  • Lib: Async, do not ignore unhandled exceptions

2.8 (2016-06-16)


  • Compiler: allow dynlink of precompiled javascript file

  • Compiler: Improve tailcall optimization

  • Compiler: Improve pretty mode

  • Compiler: More inlining and static evaluation

  • Compiler: Better source map support, to leverage resolve_variable_names in chrome DevTools

  • Compiler: preserve as much as possible the initial OCaml variable names

  • Lib: synchronize with tyxml 4.0.0

  • Lib: convert string/bigstring to/from typed_array

  • Lib: add Tyxml_js.Register API.

  • Lib: Support for Core_kernel and Async_kernel (32bit only).

  • Lib: Mutation observer.

  • Runtime: bigstring, caml_int32_bits_of_float, ..

  • Runtime: better nodejs integration


  • Support for OCaml 4.03

  • Toplevel with ppx syntax

Bug fixes

  • Compiler: Fix float printing

  • Compiler: fix separate compilation

2.7 (2016-01-25)


  • Syntax: ppx_deriving

  • Compiler: Add custom_header ability to jsoo generate file (Edgar Aroutiounian)

  • Compiler: Bytecode parsing, improved performance

  • Lib: add geolocation API (Stéphane Legrand)

  • Lib: add Mutation observers API (Stéphane Legrand)

  • Lib: add Jstable module (Drup)

  • Lib: add WebWorker API (Grégoire Henry)

  • Lib: Allow to customize 'in_channel' with specific 'refiller' (Grégoire Henry)

  • Lib: Synchronized tyxml 3.6.0


  • Compiler: Fix compilation of the [match with exception] construct

  • Compiler: fix compat with the upcoming ocaml 4.03

  • Lib: Tyxml_js, discrepancy between Firefox and Chromium

  • Lib: various small fixes

  • Runtime: Fix Big_int.square_big_int

  • Runtime: graphics, fix draw_image with transparent pixel

  • Ppx: fix for merlin

2.6 (2015-07-15)


  • Compiler: Findlib is optional

  • Compiler: improvement of sourcemap support (ie: inlinned sourcemap)

  • Compiler: Support for separate compilation (compile cm{o,a} -> js)

  • Compiler: more inlining

  • Syntax: new ppx syntax

  • Syntax: js object literal (camlp4 + ppx)

  • Runtime: support for Dynlink

  • Runtime: Support for upcoming release of Bin_prot, Core_kernel, Async_kernel

  • Lib: add requestAnimationFrame

  • Lib: complete Js.Math

  • Lib: complete xmlHttpRequest


  • Drop support for 3.12


  • Runtime: Fix caml_hash

  • Lib: fix tyxml + svg

  • Lib: various Api fixes

2.5 (2014-09-30)


  • Compiler: SourceMap improvement

  • Compiler: remove registration of unused named value (wrt runtime)

  • Compiler: Smarter inlining, Constant sharing, Switch generation

  • Lib: Dom binding: *AttributeNS, AttributeNode, borderRadius

  • Runtime: improve performance of string, array allocation

  • Misc: enable safestring for OCaml 4.02

  • Commandline: switch to Cmdliner. Better -help + manpage


  • Compiler: workaround a bug in ocaml 4.02 wrt debug section.

  • Compiler: bug when generating minified JavaScript.

  • Runtime: fix Obj.tag

  • Runtime: fix internalmod wrt ocaml4.02

2.4.1 (2014-08-28)


  • Compiler: restore compatibility with ocaml 4.02

  • Runtime: fix caml_hash, Math.imul may give wrong results (#215)

  • Lib: Graphics_js, update text drawing baseline

  • Lib: Fix overuse of FormData in XmlHttpRequest (Tomohiro Matsuyama #214)

2.4 (2014-08-08)


  • Runtime: support for num (Ryan Goulden)

  • Lib: initial support for Dom_svg

  • Lib: introduce Jsonp module

  • Lib: introduce JSON object binding

  • Lib: introduce DomContentLoaded

  • lib: introduce eventSource

  • Lib: introduce js_of_ocaml.toplevel package

  • Lib: various improvement: textContent,outerHTML,unload event,css properties

  • Lib: complete binding of Js.array

  • Lib: change signature of Sys_js.register_autoload

  • Lib: sync js_of_ocaml.tyxml with latest tyxml

  • Tools: helpers to build toplevel: jsoo_mktop, jsoo_mkcmis


  • Compiler: generate js files with default permission, was 0o600 (#182) (Daniel Bünzli)

  • Syntax: fix typing of method arguments

  • Runtime: fix behaviour of Sys.argv (Tomohiro Matsuyama)

  • Runtime: fix caml_js_meth_call

  • Compiler: fix assert false when deadcode is off

  • Compiler: fix compilation of Js.debugger

2.3 (2014-06-30)


  • Lib: remove deprecated Event_arrow

  • Lib: introduce js_of_ocaml.tyxml

  • Lib: introduce js_of_ocaml.weak (that loads weak.js) and remove predicate joo_weak

  • Lib: introduce js_of_ocaml.log (Lwt logger)

  • Lib: Dom_html.{range,selection} (Enguerrand Decorne)


  • Compiler: fix traduction of Ult binop (#177)

  • Compiler: fix the build of compiler.{cmxs,cma} (Stéphane Glondu)

  • Compiler: fix traduction of logical shift right

  • Runtime: fix marshaling (#176)

  • Meta: update predicates (joo_* -> jsoo_*)

  • Lib: fix class type Dom_html.optionElement

2.2 (2014-05-15)


  • Runtime: improve blit_string perf

  • Compiler: option to warn about unused js variable

  • Lib: audio/videoElement


  • Syntax: catch exception in syntax extension (#158)

  • Compiler: compat with Node.js (global object) (#160)

  • Runtime: fix graphics.js

  • Lib: fix Dom.event interface

2.1 (2014-04-28)


  • Runtime: bigarray comparison

  • Compiler: allow to embed directory with -file dir_name=ext1,ext2:dest_path

  • Compiler: can now output embedded files in a different js file

  • Lib:

  • Lib: Js.Unsafe.expr to embed JavasScript expression to be used instead of Js.Unsafe.variable (or eval_string)

  • Lib: Sys_js.js_of_ocaml_version && Sys_js.file_content

  • OCamlbuild plugin: Add the OASIS support, document the API and add the tags sourcemap (included in the meta-tag debug) and tailcall (#148) (by Jacques-Pascal Deplaix)


  • Syntax: Better type constraint (#84)

  • Compiler: caml_failwith primitive was sometime missing (#147)

  • Compiler: variable names used outside a program were not marked as reserved (#146)

  • Lib: fix WebGl interface

2.0 (2014-04-11)


  • Compiler: generate shorter variable names

  • Parsing and minifying of external javascript file (ie: runtime) (by Hugo Heuzard)

  • Compiler: JavaScript strict mode enabled

  • Runtime: add support for recursive module (by Hugo Heuzard)

  • Compiler: use trampoline to implement tailcall optim (by Hugo Heuzard)

  • Improved OCaml toplevel UI (by Hugo Heuzard)

  • Toplevel: support dynamic loading of cmo and cma files

  • Runtime: add Bigarray support (contributed by Andrew Ray)

  • Library: switch from "float Js.t" to just "float" for typing JavaScript numbers

  • Compiler: Add javascript file lookup using findlib (+mypkg/myfile.js will read myfile.js from mypkg findlib directory) (by Hugo Heuzard)

  • Compiler: improve missing primitives & reserved name detection (by Hugo Heuzard)

  • Compiler: static evaluation of constant ("staticeval" optimisation) (by Hugo Heuzard)

  • Compiler: share constants (by Hugo Heuzard)

  • Compiler: alias primitives (by Hugo Heuzard)

  • Compiler: complete javascript ast (by Hugo Heuzard)

  • Compiler: 'caml_format_int %d x' compiles to ""+x (by Hugo Heuzard)

  • Add JavaScript file in META (to be used with ocamlfind) (by Hugo Heuzard)

  • Add Ocamlbuild plugin js_of_ocaml.ocamlbuild (by Jacques-Pascal Deplaix)

  • Add/Install classlist.js, weak.js

  • Add Url.Current.protocol (by Vicent Balat)

  • Dependency: deriving instead of deriving-ocsigen

  • Runtime: log wrong string encoding issues to the console (by Hugo Heuzard)

  • Add compiler_libs (by Pierre Chambart)

  • Compile syntax extension to native code as well (by Hugo Heuzard)

  • Add a JavaScript parser (extracted from facebook/pfff)

  • Compiler: remove redundant 'var' (by Hugo Heuzard)

  • Compiler: improve compact mode, remove unnecessary space, semicolon

  • Runtime: Support in_channel and out_channel (by Hugo Heuzard)

  • Compiler: option to embed files into the generated js such files can be read using open_in (by Hugo Heuzard)

  • Runtime: add cache for method lookup (by Hugo Heuzard)

  • Compiler: experimental sourcemap support (by Hugo Heuzard)

  • JavaScript Errors are now wrapped inside OCaml exceptions (by Hugo Heuzard)


  • Compiler: js file is not create in case of error (by Hugo Heuzard)

  • Fix compatibility when using type covn (by Hugo Heuzard)

  • Fix md5 : incorrect for string where (length % 64) E 56..59 (by Grégoire Henry)

  • Fix caml_js_new: when called with more than 8 arguments

  • Address a number of integer overflow issues (by Hugo Heuzard)

  • Fix float comparisons (NaN was not compared correctly)

1.4 (2013-12-03)


  • Add missing primitives for OCaml 4.01

  • Improved Dom bindings (Hugo Heuzard and many other contributors)

  • Add -linkall option to keep all provided primitives (Pierre Chambard)

  • Improved tail-call optimization (Hugo Heuzard)

  • Added optimization levels: -o {1,2,3} (Hugo Heuzard)


  • Fixed some incorrect Dom bindings

  • Fixed hypot primitive (Pierre Chambard)

  • Fixed tail call optimization bug (some incorrect code was generated when the number of arguments did not match the number of function parameters)

  • Fixed a bug with empty strings

  • Fixed weak.js (primitives for Weak module)

1.3 (2012-11-28)


  • Runtime and toplevel updates to support OCaml 4.0

  • Add WebSocket bindings

  • Added -debuginfo option to output source code location information (patch by Kensuke Matsuzaki)

  • Dom_html: added change, input and hashChange event bindings

  • Adding Lwt_js_events.async_loop and buffered_loop


  • Fix array and string blitting with overlapping regions

  • Url module: fix encoding of '+'

  • Library: use 'this' instead of 'window' for better portability

  • Dom_html: fix creation of elements with type or name attribute under IE 9

  • Compiler: small fix to bytecode parsing that could result in incorrect generated code

  • Dom_html: fix mouse wheel event bindings

  • Dom: fix the type of item methods

  • Deriving_json: tail-recursive serialisation of lists (by Hugo Heuzard)

  • Deriving_json: fix parsing of float arrays and polymorphic variants (by Hugo Heuzard)

1.2 (2012-06-02)


  • Improvements in the data-flow solver

  • Add Dom_html.window##onscroll

  • Dom_events.listen: handler should return boolean

  • Add DOM drag/drop events


  • Fix #284

  • Fix return type of window##open_

1.1.1 (2012-03-15)


  • add webgl example


  • Url parsing.

  • webgl binding types

1.1 (2012-02-24)


  • Lots of new dom bindings

  • WebGL

  • Typed arrays

  • Many speed improvement (marshal, strings, regexps)

  • Many bug fixed


  • Add -I option to select directories containing cmi files

  • Fix compilation of mutually recursive functions occurring in loops

  • In Javascript output, parenthesize numbers when followed by a dot

  • Fix order of evaluation bug

  • Fix compilation of loops in 'try ... with' body (close #263)


  • hyperbolic tree example

1.0.9 (2011-11-30)

  • Bugfixe in polymorphic comparison.

1.0.8 (2011-11-25)

  • Compatibility with deriving-0.3

  • Libraries:

    • Adding Event_arrows.iter

    • Events: adding Dom_html.stopPropagation and ?propagate parameter in Event_arrows

1.0.7 (2011-11-18)


  • Add Dom_html.buttonPressed

  • Add functions to downcast Dom_html.event into mouseEvent, keyboardEvent, ...

  • Add Dom.document.adoptNode

  • removed function, not supported by all browsers

  • Allow to test the button associated to a Dom_html.mouseEvent

  • Add localStorage and sessionStorage api


  • Deriving_json: fix string (un)marshaling (was broken for byte > 127)

  • Do not emit string escape sequence \v (not supported by IE8)

  • Removed incorrect optimization of !(x < y) into (x ># y)

  • Allow compilation on win32/msvc

  • Open all files in binary mode

1.0.6 (2011-09-28)


  • add Dom_html.iFrameEliom##width

  • add Dom_html.window##scroll

  • add Dom.document##importNode


  • browser compatility for and check_headers (XmlHttpRequest.send).

1.0.5 (2011-09-21)


  • XmlHttpRequest: allow to cancel ta XHR after receiving the HTTP headers

  • Added the [CSS.Angle] module to handle angles in CSS


  • array_get/set bound check

1.0.4 (2011-09-07)


  • History API

  • improvements of CSS module

  • Add coercion and attribute manipulation functions in Dom module


  • fix typo in 'greater than or equal to'

  • marshaling, unmarshaling and comparison are not recursive anymore: avoid stack overflow

  • use custom formatter to pretty print Javascript code to avoid newlines where it is forbidden.

  • fix type of Dom.nodeList.item (was optdef, is now opt)

  • fixes for internet explorer.

  • fixes for bug exposed by Berke Durak's tool jsure.

1.0.3 (2011-07-13)


  • Add a CSS module

  • export Form.form_elements

  • add onsubmit method to Dom_html.formElement

  • add classList property to dom elements


  • 'caml_int_of_string' was incorrect for negative number

  • Fixed misparenthesized Javascript 'new' expressions

1.0.2 (2011-04-13)


  • Switch licence to LGPL

  • API to generate a function instead of a standalone program

  • option to compile an OCaml toplevel


  • Add an optional JSON deriving class

  • Add Math.random binding

  • Add scrollWidth/scrollHeight element methods to the DOM

  • Add coercion function Dom_html.CoerceTo.element

  • Renaming functions in XmlHttpRequest:

    • send -> perform

    • send_string -> perform_raw_url


  • fix compilation of Int32/Nativeint

  • fix compilation of self-recursive functions in loops

  • fix to File module for when there is no FileReader class in the host browser

  • fixed big in weak support

1.0.1 (2011-01-26)

  • Allow use of Lwt.pause.

  • Split ocamlfind packages in two: syntax and library.


  • conversion of Int64 to string.

  • typos.

1.0 (2010-12-13)

Initial release


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