tool is the js_of_ocaml executable.

assets_root indicates the path with respect to which page assets are are B0_std.Fpath.rerooted. Assets that are not prefixed by assets_root are simply copied at the toplevel of the build dir.

The type for js_of_ocaml compilation either whole program compilation mode for runtime efficiency and minimality or `Separate for build time efficiency.

compilaton_mode is the js_of_ocaml compilation mode. Defaults to `Whole.

FIXME this should likely be a store key or something similar to the way we handle built code for OCaml.

compile are options added to the js_of_ocaml compile subcommand. Defaults to B0_std.Cmd.empty.

The type for specifying source maps desires.

FIXME Like compilation_mode this should possibly be associated the build.

source_map is the source map option. Defaults to Some `File.

tag indicates the entity is related to js_of_ocaml.

toplevel should be true to embed toplevel support in the js executable.

link_opts are options added to the js_of_ocaml link subcommand.

exe exename is a JavaScript "executable" file named exename.

• doc is the unit doc string.
• requires are the OCaml libraries required to compile the JavaScript. Added to the unit meta as B0_ocaml.requires.
• meta is added to the
• public is the visibility status. Added to the unit meta as B0_meta.public's meta.
• name is the name of the unit (defaults to name with . replaced by -).
• srcs are the executable sources. All files with extension .ml, .mli and .js are considered for compiling and linked in the JavaScript file.
• wrap allows to extend the build procedure you must call the given build procedure.

html_page ?js_file page constructs in the unit directory an HTML file named page.html, a JavaScript file named js_file (defaults to page.js) and copies over (or generates) B0_file_exts.www files of srcs as follows:

• page.html, if a file exists with that name in srcs, this file is used. Otherwise a minimal HTML document linking pagename.js and .css assets is generated.
• js_file is compiled by considering all files with extension .ml, .mli and .js and linked against required libraries requires.

• The files B0_file_exts.www in srcs minus .js files are copied over to the unit directory. If these files can be rerooted to the build directory according to assets_root they are copied in a hierarchy otherwise they are copied at the root of the directory

  FIXME. Make that comprehensible.

  FIXME. A competing idea was to have a notion of root induced by B0_srcs selection. See the commented stuff there. This is likely something that will play better with generated assets. It's also sligthly borderline with deployements.

The other arguments are as follows:

• doc is the unit doc string.
• meta is the initial metadata.
• requires are the OCaml libraries required to compile the JavaScript.
• name is the name of the unit (defaults to pagename).
• jsname is the basename of the JavaScript file, defaults to pagename.
• srcs are the sources to lookup, see above.
• wrap allows to extend the build procedure you must call the given build procedure. TODO maybe remove once we have good Build fragments.

compile m ~source_map ~jss ~byte ~o compiles the JavaScript files jss and byte code object or executable byte to the JavaScript file o.

link m ~opts ~jss ~o links the JavaScript files jss to o with options opts.

build_runtime m ~jss o writes a standalone runtime with JavaScript files jss to o.

copy_assets m srcs ~exts ~assets_root ~dst copies srcs with extensions in exts to dst. If assets_root is specified indicates the path w.r.t. which assets are B0_std.Fpath.rerooted. Assets that are not prefixed by assets_root are simply copied at the toplevel of dst.

FIXME. Not a good idea to ready them inside. But all this needs a good review.

write_page m ~title ~o writes to file o a full HTML document whose body contains only a B0_html.El.noscript element that entices the user, in english, to enable JavaScript. title defaults to the basename of o without its extension, for the other arguments and more information see B0_html.El.basic_page.