wacl

This is a distribution of Tcl and some extensions to Webassembly. The code is available under the 3-clause BSD license (see "LICENSE"). It compiles the tcl library and exposes some C api calls. At runtime a Tcl interpreter is created and initialized, and the event loop is setup to run via emscripten_set_main_loop (see opt/waclAppInit.c). Furthermore there is an extension package "wacl", which provides commands:

• wacl::dom (with honors to Aidan Hobson's emtcl, where the code comes from)
  • manipulate the browser dom
• wacl::jscall
  • call prehooked javascript functions from Wacl

Currently supported is tcl - core_8_6_6. It isTcl comes with a toy DOM library as a demo. See EXTRAS.

BUILD

To build it, you need the emscripten sdk on your path:

$ make waclprep  # One off prep - tcl-core download, hacks.patch application and autoconf
$ make config    # create build directory and run emconfigure tcl/unix/configure
$ make [all]     # create the library and emtcl.js
$ make install   # copy emtcl.js to ../www/js/

If you want to totally reset all build files in ./tcl/ and start again:

$ make reset

This removes all changes and untracked files in there, so be careful!

There is a target to recreate the patch, if you changed anything important in tcl/

$ make patch

It downloads tcl-core (it not already present), extracts it and runs diff between it and tcl/. The result is the patch that is applied above via "make tclprep"

EXTRAS

Wacl comes with a toy DOM library compiled into it by default as a demonstration of how one could do interesting things.

It currently is a command of the form dom attr|css selector key val. It sets the appropriate key in either the attribute or style dictionary of each element returned by the selector. It will return the number of elements modified. Note that style keys are in their camelcase form (backgroundColor vs background-color) as the styles are changed in the element style dictionary.

You can see the code in opt/wacl.c. It is compiled along with the other commands in the "wacl" package and loaded into the default interpreter at startup.