package js_of_ocaml

  1. Overview
  2. Docs
Compiler from OCaml bytecode to JavaScript

Install

Dune Dependency

ocsigen.org Readme Changelog GPL-2.0-or-later; LGPL-2.1-or-later WITH OCaml-LGPL-linking-exception License Edit opam file Versions (50)

Authors

  1. O
    Ocsigen team <dev@ocsigen.org>

Maintainers

  1. O
    Ocsigen team <dev@ocsigen.org>

Sources

js_of_ocaml-5.6.0.tbz
sha256=8435f02633a17ef6c8a1a3171a6537fdb206c00c4fb7d4ca54250df6daf6c23f
sha512=a9556ec69a90ea8ff9b6ea1ab983815e39f6703c7da6df24524e023d76fb04790ffed8666a2671f42c31bca15013a4238ae98a8c1c35d90fabdf9993565a1d99

Description

Js_of_ocaml is a compiler from OCaml bytecode to JavaScript. It makes it possible to run pure OCaml programs in JavaScript environment like browsers and Node.js

Published: 10 Jan 2024

README

Js_of_ocaml (jsoo)

Js_of_ocaml is a compiler from OCaml bytecode to JavaScript. It makes it possible to run pure OCaml programs in JavaScript environment like browsers and Node.js.

  • It is easy to install and use as it works with an existing installation of OCaml, with no need to recompile any library.

  • It comes with bindings for a large part of the browser APIs.

  • According to our benchmarks, the generated programs runs typically faster than with the OCaml bytecode interpreter.

  • We believe this compiler will prove much easier to maintain than a retargeted OCaml compiler, as the bytecode provides a very stable API.

Js_of_ocaml is composed of multiple packages:

  • js_of_ocaml-compiler, the compiler.

  • js_of_ocaml-ppx, a ppx syntax extension.

  • js_of_ocaml, the base library.

  • js_of_ocaml-ppx_deriving_json

  • js_of_ocaml-lwt, lwt support.

  • js_of_ocaml-tyxml, tyxml support.

  • js_of_ocaml-toplevel, lib and tools to build an ocaml toplevel to javascript.

Requirements

See opam file for version constraints.

optional

Toplevel requirements

  • tyxml, reactiveData

  • ocp-indent: needed to support indentation in the toplevel

  • higlo: needed to support Syntax highlighting in the toplevel

  • cohttp: needed to build the toplevel webserver

Installation

Opam

opam install js_of_ocaml js_of_ocaml-compiler js_of_ocaml-ppx

Usage

Your program must first be compiled using the OCaml bytecode compiler ocamlc. JavaScript bindings are provided by the js_of_ocaml package. The syntax extension is provided by js_of_ocaml-ppx package.

ocamlfind ocamlc -package js_of_ocaml -package js_of_ocaml-ppx -linkpkg -o cubes.byte cubes.ml

Then, run the js_of_ocaml compiler to produce JavaScript code:

js_of_ocaml cubes.byte

Features

Most of the OCaml standard library is supported. However,

  • Most of the Sys module is not supported.

Extra libraries distributed with OCaml (such as Thread) are not supported in general. However,

  • Bigarray: bigarrays are supported using Typed Arrays

  • Num: supported

  • Str: supported

  • Graphics: partially supported using canvas (see js_of_ocaml-lwt.graphics)

  • Unix: time related functions are supported

Tail call is not optimized in general. However, mutually recursive functions are optimized:

  • self recursive functions (when the tail calls are the function itself) are compiled using a loop.

  • trampolines are used otherwise. More about tail call optimization.

Effect handlers are supported with the --enable=effects flag.

Data representation

Data representation differs from the usual one. Most notably, integers are 32 bits (rather than 31 bits or 63 bits), which is their natural size in JavaScript, and floats are not boxed. As a consequence, marshalling, polymorphic comparison, and hashing functions can yield results different from usual:

  • marshalling of floats is not supported (unmarshalling works);

  • the polymorphic hash function will not give the same results on datastructures containing floats;

  • these functions may be more prone to stack overflow.

Ocaml javascript
int number (32bit int)
int32 number (32bit int)
nativeint number (32bit int)
int64 Object (MlInt64)
float number
string string or object (MlBytes)
bytes object (MlBytes)
"immediate" (e.g. true, false, None, ()) number (32bit int)
"block" array with tag as first element (e.g. C(1,2) => [tag,1,2])
array block with tag 0 (e.g. [\|1;2\|] => [0,1,2])
tuple block with tag 0 (e.g. (1,2) => [0,1,2])
record block (e.g. {x=1;y=2} => [0,1,2])
constructor with arguments block (e.g. C (1, 2) => [tag,1,2])
module block
exception and extensible variant block or immediate
function function

Toplevel

Contents of the distribution

Filename Description
LICENSE license and copyright notice
README this file
compiler/ compiler
examples/ small examples
lib/ library for interfacing with JavaScript APIs
ppx/ ppx syntax extensions
runtime/ runtime system
toplevel/ web-based OCaml toplevel

Dependencies (4)

  1. ppxlib >= "0.15"
  2. js_of_ocaml-compiler = version
  3. ocaml >= "4.08"
  4. dune >= "3.7"

Dev Dependencies (4)

  1. odoc with-doc
  2. re >= "1.9.0" & with-test
  3. ppx_expect >= "v0.14.2" & with-test
  4. num with-test

  1. alba >= "0.4.1"
  2. archetype >= "1.2.7"
  3. async_js >= "v0.13.0" & != "v0.15.0"
  4. binaryen >= "0.3.0" & < "0.12.1"
  5. bls12-381-js
  6. bls12-381-js-gen
  7. bonsai >= "v0.15.1"
  8. brr = "0.0.3"
  9. brr-lwd
  10. chartjs
  11. chartjs-annotation
  12. chartjs-colorschemes
  13. chartjs-datalabels
  14. chartjs-streaming
  15. cohttp-lwt-jsoo >= "2.5.0"
  16. coinst
  17. cordova
  18. cordova-plugin-background-mode
  19. cordova-plugin-battery-status
  20. cordova-plugin-local-notifications
  21. cordova-plugin-sim-card
  22. dream >= "1.0.0~alpha5"
  23. eliom = "6.3.0" | >= "6.5.0" & < "6.8.0" | >= "6.9.2" & < "6.10.1" | >= "7.0.0"
  24. eris
  25. ezjs_ace
  26. ezjs_blockies
  27. ezjs_cleave
  28. ezjs_d3pie
  29. ezjs_fetch < "0.2"
  30. ezjs_min < "0.2"
  31. ezjs_odometer
  32. ezjs_push < "0.2"
  33. ezjs_qrcode
  34. ezjs_recaptcha
  35. ezjs_timeline
  36. fmlib_js
  37. gen_js_api < "1.0.7"
  38. github-jsoo < "4.0.0"
  39. graphv_font_js
  40. graphv_webgl_impl
  41. hardcaml = "1.2.0"
  42. hardcaml-examples >= "0.3.0"
  43. hardcaml-framework
  44. incr_dom >= "v0.15.1"
  45. incr_dom_interactive != "v0.15.0"
  46. incr_dom_keyboard
  47. incr_dom_partial_render != "v0.15.0"
  48. incr_dom_sexp_form != "v0.15.0"
  49. incr_dom_widgets
  50. integers_stubs_js
  51. iocamljs-kernel = "0.4.5"
  52. irmin-indexeddb >= "2.0"
  53. joolog
  54. js_of_ocaml-lwt = "5.6.0"
  55. js_of_ocaml-ppx = "5.6.0"
  56. js_of_ocaml-ppx_deriving_json = "5.6.0"
  57. js_of_ocaml-tyxml = "5.6.0"
  58. js_of_ocaml-webgpu
  59. js_of_ocaml-webidl
  60. js_of_ocaml_patches
  61. json-data-encoding-browser
  62. jsonoo
  63. jsoo-react
  64. jsoo_broadcastchannel >= "2.0.0"
  65. jsoo_storage >= "1.0.1"
  66. kkmarkdown
  67. ldp_js
  68. leaflet
  69. learn-ocaml >= "0.12"
  70. liquidsoap-js
  71. lp-glpk-js
  72. nanoid
  73. node_of_ocaml
  74. nuscr < "1.1.0"
  75. ocaml-gist
  76. ocp_reveal
  77. ocplib-json-typed-browser
  78. ocsigen-start >= "1.7.0" & != "2.15.1" & < "2.16.0"
  79. ocsigen-toolkit >= "3.3.1"
  80. ojs-base >= "0.6.0"
  81. ojs_base
  82. picos < "0.5.0"
  83. picos_meta
  84. plotly
  85. polynomial >= "0.4.0"
  86. ppx_css >= "v0.15.1"
  87. ppx_jsobject_conv >= "0.6.0" & != "0.9.3"
  88. promise_jsoo
  89. prr
  90. rpclib-js
  91. sherlodoc
  92. spin >= "0.8.0"
  93. tezt >= "3.1.0"
  94. timedesc-tzlocal-js
  95. timmy-jsoo
  96. tyxml-lwd >= "0.2"
  97. vg = "0.9.4"
  98. virtual_dom != "v0.15.0"
  99. virtual_dom_toplayer
  100. webtest-js
  101. wikitext
  102. xmldiff_js
  103. xtmpl = "0.18.0"
  104. xtmpl_js

Conflicts

None

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