Femto-Emacs

Tiny emacs clone that can be configured with femtolisp

ncurses femtoemacs requires the ncurses library. This library

allows one to treat a text terminal as an editor window. You must download, build and install ncurses. You can obtain it here.

In English, some people add marks or glyphs to certain letters. For instance, instead of writing "facade", they write "façade". On the same token, they write "café" in lieu de "cafe". If you need or like diacritics, you must compile the libncurses library thus:

% cd ncurses-6.0/
% ./configure --enable-widec
% make
% sudo make install

MAC OS-X

The developers of femtoemacs assume that you have placed libncursesw.a here:

/usr/local/lib/libncursesw.a

Therefore, enter the folder where you unpacked the ncursesw-6.0 distribution archive, and copy the libncursesw.a file to /usr/local/lib/ as shown below.

% cd ncurses-6.0
% cd lib
% sudo cp libncursesw.a /usr/local/lib/

After installing libncursesw, enter the folder Femto-Emacs/femto/ and build the editor for Macistosh:

% cd ~/Femto-Emacs/
% make -f Makefile.macosx
% sudo make -f Makefile.macosx install

Option as Meta key

Enter the Terminal menu (right of the bitten Apple logo at the upper left corner of the screen), open Preferences, choose Profiles and tick the Use-Option-as-Meta-key' box. Finally, you can test the editor in loco:

% femto test.scm

You can remove Femto-Emacs from your system with the following command:

% sudo sh uninstall.sh

Linux

Do not use apt-get to install ncurses, because the repositories are old. Instead, download a recent source distribution and build it thus:

% cd ncurses-6.0
% ./configure --enable-widec
% make
% sudo make install

After installing ncursesw, you can make the editor:

% cd ~/Femto-Emacs/
% make
% sudo make install 

Test the editor in loco:

% femto test.scm

You can remove Femto-Emacs from your system with the following command:

% sudo sh uninstall.sh

Hopefully, you will be able to use femto anywhere in your computer. You will notice that it will pop up much faster than emacs.

Short term goals

Binaries for Windows. Since most Windows users don't know how to compile applications from source, we need to provide binaries. If you want to contribute with mingw binaries, please let us know.

Documentation. We intend to provide good documentation for people who want to extend the editor or adapt femtolisp for this new role of scripting language.

Lisp Interaction Mode

There are two way to interact with Femto Lisp from inside FemtoEmacs.

At a command prompt: Enter C-o and type a lisp command followed by return. The result is inserted into the current buffer at the cursor location

Inside the actual buffer: Place the cursor on the openning or closing bracket ( or ). This will define a block. Now enter ESC-]. The code will be copied to the FemtoLisp interpreter and the result inserted into the buffer. This is very useful for trying out bits of lisp code when developing Emacs extensions.

Integration of Femto with Femtolisp to be become FemtoEmacs

Femtolisp required three modifications, in order to work as a script language for femto. In the file flcall.c you will be find the functions callLisp and initLisp, that are used for calling a Lisp function from C and initializing Lisp, respectively. In file interface2editor.c you will find all functions directly related to the editor.

It is also necessary to generate a boot and a compiler without a Read Eval Print Loop. This is done in file mkeditorboot.lsp, that has three lines:

(load "femtosystem.lsp")            ;; system without Read Eval Print Loop
(load "compiler.lsp")               ;; compiler exactly like femtolisp compiler
(make-system-image "femto.boot")    ;; generate femto.boot

The only difference between femto.boot and flisp.boot is in function __start, that does nothing in the editor, besides initializing the global environment.

(define (__start argv)
  (__init_globals))

In femtolisp, this funcion is defined in system.lsp, and implements the Read Eval Print Loop:

(define (__start argv)
  (__init_globals)
   (if (pair? (cdr argv))
       (begin
	     (set! *argv* (cdr argv))
         (set! *interactive* #f)
         (__script (cadr argv)))
       (begin
	     (set! *argv* argv)
         (set! *interactive* #t)
         (princ *banner*)
         (repl)))
  (exit 0))

The __start function is called in flcall.c:

(void)fl_applyn(1, symbol_value(symbol("__start")),
	            argv_list(argc, argv));