package js_of_ocaml-ppx

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  2. Docs
Compiler from OCaml bytecode to JavaScript

Install

Dune Dependency

Authors

Maintainers

Sources

js_of_ocaml-4.0.0.tbz
sha256=df02f819e5b2f48234af2b3e3e7c9781afa8212f8bece7ebcfbd8358b394495e
sha512=92e822849c8be14ce0428f7f4be3991449f76e65d408073a5b8b9674ba2d099439027aa11618b603c7ee31a179cf6976d54a929917a69b269425f0367926c200

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: 26 Jan 2022

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,

  • Weak semantic cannot be implemented using JavaScript. A dummy implementation is provided.

  • 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.

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])
contructor 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 >= "0.15.0"
  2. js_of_ocaml = version
  3. ocaml >= "4.04"
  4. dune >= "2.9"

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

Used by (81)

  1. alba >= "0.4.1"
  2. archetype >= "1.2.7"
  3. async_js >= "v0.10.0" & < "v0.16.0"
  4. atable
  5. binaryen >= "0.3.0" & < "0.12.1"
  6. bls12-381-js
  7. bls12-381-js-gen
  8. bonsai = "v0.15.1"
  9. catala >= "0.3.0" & < "0.9.0"
  10. chartjs
  11. chartjs-annotation
  12. chartjs-colorschemes
  13. chartjs-datalabels
  14. chartjs-streaming
  15. cohttp-lwt-jsoo = "1.2.0" | >= "2.5.0"
  16. d3 >= "0.3.0"
  17. dream >= "1.0.0~alpha5"
  18. eliom >= "6.3.0" & < "6.8.0" | >= "6.9.2" & < "6.10.1" | >= "7.0.0"
  19. ezjs_ace
  20. ezjs_blockies
  21. ezjs_cleave
  22. ezjs_cytoscape
  23. ezjs_d3pie
  24. ezjs_fetch < "0.2"
  25. ezjs_jquery
  26. ezjs_min
  27. ezjs_odometer
  28. ezjs_push < "0.2"
  29. ezjs_qrcode
  30. ezjs_recaptcha
  31. ezjs_timeline
  32. fmlib_js
  33. github-jsoo < "3.0.1"
  34. graphv_font_js
  35. graphv_webgl_impl
  36. incr_dom >= "v0.10.0" & < "v0.16.0"
  37. incr_dom_interactive < "v0.16.0"
  38. incr_dom_keyboard
  39. incr_dom_partial_render < "v0.16.0"
  40. incr_dom_sexp_form < "v0.16.0"
  41. incr_dom_widgets
  42. incr_select >= "v0.10.0" & < "v0.12.0"
  43. irmin-indexeddb >= "2.0"
  44. js_of_ocaml-lwt = "4.0.0"
  45. js_of_ocaml-toplevel = "4.0.0"
  46. js_of_ocaml-tyxml = "4.0.0"
  47. js_of_ocaml-webgpu
  48. js_of_ocaml-webidl
  49. jsonoo < "0.3.0"
  50. jsoo-react
  51. jsoo_broadcastchannel >= "2.0.0"
  52. jsoo_storage >= "1.0.1"
  53. kkmarkdown
  54. ldp_js
  55. leaflet
  56. learn-ocaml >= "0.12"
  57. liquidsoap-js
  58. lp-glpk-js
  59. memtrace_viewer >= "v0.15.0"
  60. monaco_jsoo
  61. nuscr < "1.1.0"
  62. ocp_reveal
  63. ojs_base
  64. opam2web >= "2.0"
  65. plotly
  66. polynomial >= "0.4.0"
  67. ppx_css < "v0.16.0"
  68. promise_jsoo < "0.4.2"
  69. rpclib-js
  70. scaml >= "1.5.0"
  71. spin >= "0.8.0"
  72. timedesc-tzlocal-js
  73. timmy-jsoo
  74. tyxml-lwd >= "0.2"
  75. vg >= "0.9.0" & < "0.9.5"
  76. virtual_dom >= "v0.10.0" & < "v0.16.0"
  77. vue-jsoo < "0.3"
  78. webtest-js
  79. xmldiff_js
  80. xtmpl >= "0.17.0" & < "0.19.0"
  81. xtmpl_js

Conflicts

None