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INTRODUCTION

Little is a compiled-to-byte-code language that draws heavily from C and Perl. From C, Little gets C syntax, simple types (int, float, string), and complex types (arrays, structs). From Perl, Little gets associative arrays and regular expressions (PCRE). And from neither, Little gets its own simplistic form of classes.

The name "Little", abbreviated as simply "L", alludes to the language's simplicity. The idea was to distill the useful parts of other languages and combine them into a scripting language, with type checking, classes (not full-blown OO but useful none the less), direct access to a cross-platform graphical toolkit, and a library drawn from Perl and the standard C library.

L is built on top of the Tcl/Tk system. The L compiler generates Tcl byte codes and uses the Tcl calling convention. This means that L and Tcl code may be intermixed. More importantly, it means that Little may use all of the Tcl API and libraries as well as TK widgets. The net result is a type-checked scripting language which may be used for cross-platform GUIs.

Little is open source under the same license as Tcl/TK (BSD like) with any bits that are unencumbered by the Tcl license also being available under the Apache License, Version 2.0.

Little is based on interim Tcl and Tk releases http://core.tcl.tk/tcl/info/497b93405b3435aa and http://core.tcl.tk/tk/info/407bae5e576b5ef7.

PREREQUISITES

  • bison
  • flex
  • libxft2-dev (Linux only)

COMPILING L

Little can be built with or without Tk. Without Tk, you get only an tclsh executable named "L". With Tk, you get that and a version of wish with Little named "L-gui" (on OS X, an application bundle is created instead). The accompanying Makefile builds L and L-gui for Linux, OS X, and Windows.

Because Little is integrated into Tcl/Tk, the instructions for configuring and compiling Tcl and Tk apply. See tcl/README and tk/README if you need to tweak anything. L adds Perl-compatible regular expressions (PCRE) and the --with-pcre=<path> configure option to Tcl.

A Windows build wants msys or cygwin. A make help explains the make targets.

L uses git submodules to distribute Tcl, Tk, and PCRE. To compile from source:

$ git submodule init
$ git submodule update
$ make

Extra notes for compiling on Windows

The build requires the MinGW project, available from:

http://mingw.org

If you did not already have MinGW installed, you will need to install it. Installation instructions can be found here:

http://mingw.org/wiki/Getting_Started

You should install the MSYS base system as well as the developer toolkit (they were not part of the initial basic installation at this writing).

One you have MSYS installed, you can open an MSYS window by running msys.bat as described on the Getting Started page.

In this window you will be presented with a shell (bash) prompt and you can type:

cd /c/...

where ... is the path to where you unpacked this file. Now you should be able to type:

make

INSTALLING

On Linux and Windows, a make install will install L and L-gui in /opt/little-lang (can be overridden with PREFIX=$DIR).

For OS X, Little is similarly installed, but the L-gui application bundle is copied to LGUI_OSX_INSTALL_DIR which defaults to /Applications.

DOCUMENTATION

make install will create $(PREFIX)/doc/L.html

If the build machine has groff and a postscript to PDF converter installed then you also get $(PREFIX)/doc/little.pdf.

Alternatively, see tcl/doc/l-paper for "The L Programming language" published in the Proceedings of the 13th Annual Tcl/Tk Conference.