Juicemacs.elisp

The build process of GNU Emacs generates a bunch of file that are crucial to the interpreter and you will need to first build a GNU Emacs if you want this project to do anything useful. (For example, Unicode properties and charset mappings in Emacs are all loaded from generated .el or mapping files.)

Currently, the project can fully run through the Emacs loadup.el when run in pbootstrap/pdump mode. You may try out a partially initialized environment with ../app/, which contains a simple ELisp REPL.

See ../README.html for instructions.

Juicemacs.elisp is written with the Truffle Language Implementation Framework and loosely follows how language implementations structure their code.

• party.iroiro.juicemacs.elisp.ELispLanguage defines a TruffleLanguage, feeding user input into a parser, starting code execution.
• party.iroiro.juicemacs.elisp.runtime.ELispContext is a Truffle language context.
• party.iroiro.juicemacs.elisp.runtime.ELispGlobals holds almost all the global elisp variables. It is a huge file, most of which is generated directly from Emacs source code.

• party.iroiro.juicemacs.elisp.forms holds all the built-in subroutine definitions. Most of the methods there are generated by emacs-extractor from Emacs sources and are yet to be implemented. (They currently simply throw UnsupportedOperationException.)

  The process of implementing a subroutine is quite straight-forward:

  • Find the class corresponding to the subroutine
  • Change its method signature to match the real subroutine
  • Optionally write more @Specialization methods to handle all possible types
  • Write the code

  If a subroutine is not generated yet. One will need to modify emacs-extractor and run ./gradlew :elisp:emacsGen.

  • party.iroiro.juicemacs.elisp.forms.regex contains a tiny regex engine that (I hope) conforms to the Emacs regex syntax.
• party.iroiro.juicemacs.elisp.parser holds a lexer and a parser.
• party.iroiro.juicemacs.elisp.runtime.objects holds the ELisp object definitions.
• party.iroiro.juicemacs.elisp.nodes and several classes in party.iroiro.juicemacs.elisp.runtime implements logic to run ELisp code with Truffle. One may start from party.iroiro.juicemacs.elisp.nodes.ast.ELispInterpretedNode to see how we transform a Lisp object into a dynamic AST.
• party.iroiro.juicemacs.elisp.nodes.bytecode (and the ELispBytecode class) hosts classes implementing a Emacs Lisp bytecode interpreter.