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Pull request overview
This PR adds WebAssembly (WASM) support to Eliom, allowing client code to be compiled to WASM as an alternative to JavaScript. The feature is enabled by default but can be disabled via configuration.
Changes:
- Added WASM compilation support with automatic browser detection that loads WASM when supported, falling back to JavaScript
- Extended Eliom configuration system with
enable_wasmoption and related API functions - Updated build templates (app.lib, app.exe) to compile and deploy both JS and WASM versions with dune 3.17+
Reviewed changes
Copilot reviewed 22 out of 22 changed files in this pull request and generated 9 comments.
Show a summary per file
| File | Description |
|---|---|
| src/lib/eliom_registration.server.ml | Added wasm_detection_script function that generates inline JavaScript to detect WebAssembly support and load the appropriate file |
| src/lib/eliom_common.server.ml/mli | Added enable_wasm field to sitedata record |
| src/lib/server/eliommod.ml/mli | Added default_enable_wasm configuration, XML parsing for wasm tag, and integration into parse_eliom_option(s) |
| src/lib/eliom_config.server.ml/mli | Added set_enable_wasm and get_enable_wasm API functions |
| src/lib/eliom.server.ml/mli | Added enable_wasm parameter to run function with documentation |
| pkg/distillery/templates/app.lib/dune | Added wasm mode to executables and wasm_of_ocaml configuration |
| pkg/distillery/templates/app.lib/dune-project | Bumped dune version from 3.14 to 3.17 for wasm support |
| pkg/distillery/templates/app.lib/Makefile.app | Added WASM build targets and installation steps with conditional ENABLE_WASM checks |
| pkg/distillery/templates/app.lib/Makefile.options | Added ENABLE_WASM configuration option |
| pkg/distillery/templates/app.exe/* | Similar changes as app.lib template |
| pkg/distillery/templates/basic.ppx/Makefile | Added note that WASM is not supported in this legacy template |
| pkg/distillery/templates/basic.ppx/Makefile.options | Added ENABLE_WASM option (though unused in this template) |
| dune-project, eliom.opam | Added wasm_of_ocaml-compiler dependency |
| src/ppx/ppx_eliom_utils.ml | Added optional loc parameter to type_of_out_type and related functions for better location tracking, plus OCaml 5.3.0 compatibility adjustments |
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src/lib/eliom_registration.server.ml
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| in | ||
| let script_content = | ||
| Printf.sprintf | ||
| "(function() {\n\ var script = document.createElement('script');\n\ script.defer = %s;\n\ script.async = %s;\n\ \n\ if (typeof WebAssembly === 'object' && \n\ typeof WebAssembly.instantiate === 'function') {\n\ script.src = '%s';\n\ } else {\n\ script.src = '%s';\n\ }\n\ \n\ document.head.appendChild(script);\n})();" |
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if (window?.WebAssembly?.JSTag) { ... } else { ... }
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Add wasm support.
It is activated by default, but there is an Eliom option to deactivate it.
If activated, eliom includes a small inline script that will detect if the browser is compatible and load the right file.
Templates have benn updated to compile the wasm version.
@vouillon This is ready to review but cannot be merged until ocsigen/js_of_ocaml#2151 is released
See also ocsigen/ocsigen-start#699