OOP In Ficl
Parse Steps
Release History
Upgrading To 4.0

What is Ficl?

Ficl is a programming language interpreter designed to be embedded into other systems as a command, macro, and development prototyping language.

Ficl is an acronym for "Forth Inspired Command Language".

Ficl Features

Ficl is easy to port.
  • It typically takes under 2 hours to port to a new platform.
  • Ficl is written in strict ANSI C.
  • Ficl can run natively on 32- and 64-bit processors.

Ficl has a small memory footprint.
A fully featured Win32 console version takes less than 100K of memory, and a minimal version is less than half that.

Ficl is easy to integrate into your program.
Where most Forths view themselves as the center of the system and expect the rest of the system to be coded in Forth, Ficl acts as a component of your program. It is easy to export code written in C or ASM to Ficl (in the style of TCL), or to invoke Ficl code from a compiled module.

Ficl is fast.
Thanks to its "switch-threaded" virtual machine design, Ficl 4 is faster than ever—about 3x the speed of Ficl 3. Ficl also features blindingly fast "just in time" compiling, removing the "compile" step from the usual compile-debug-edit iterative debugging cycle.

Ficl is a complete and powerful programming language.
Ficl is an implementation of the FORTH language, a language providing a wide range of standard programming language features:
  • Integer and floating-point numbers, with a rich set of operators.
  • Arrays.
  • File I/O.
  • Flow control (if/then/else and many looping structures).
  • Subroutines with named arguments.
  • Language extensibility.
  • Powerful code pre-processing features.

Ficl is standards-compliant.
Ficl conforms to the 1994 ANSI Standard for FORTH (DPANS94). See ANS Required Information for more detail.

Ficl is extensible.
Ficl is extensible both at compile-time and at run-time. You can add new script functions, new native functions, even new control structures.

Ficl adds object oriented programming features.
Ficl's flexible OOP library can be used to wrap data structures or classes of the host system without altering them. (And remember how we said Ficl was extensible? Ficl's object-oriented programming extensions are written in Ficl.)

Ficl is interactive.
Ficl can be used interactively, like most other FORTHs, Python, and Smalltalk. You can inspect data, run commands, or even define new commands, all on a running Ficl VM. Ficl also has a built-in script debugger that allows you to step through Ficl code as it is executed.

Ficl is ROMable.
Ficl is designed to work in RAM based and ROM code / RAM data environments.

Ficl is safe for multithreaded programs.
Ficl is reentrant and thread-safe. After initialization, it does not write to any global data.

Ficl is open-source and free.
The Ficl licence is a BSD-style license, requiring only that you document that you are using Ficl. There are no licensing costs for using Ficl.

What's New In Ficl 4.0?

Ficl 4.0 is a major change for Ficl. Ficl 4.0 is smaller, faster, more powerful, and easier to use than ever before. (Or your money back!)

Ficl 4.0 features a major engine rewrite. Previous versions of Ficl stored compiled words as an array of pointers to data structure; Ficl 4.0 adds "instructions", and changes over to mostly using a "switch-threaded" model. The result? Ficl 4.0 is approximately three times as fast as Ficl 3.03.

Ficl 4.0 also adds the ability to store the "softcore" words as LZ77 compressed text. Decompression is so quick as to be nearly unmeasurable (0.00384 seconds on a 750MHz AMD Duron-based machine). And even with the runtime decompressor, the resulting Ficl executable is over 13k smaller!

Another new feature: Ficl 4.0 can take advantage of native support for double-word math. If your platform supports it, set the preprocessor symbol FICL_HAVE_NATIVE_2INTEGER to 1, and create typedefs for ficl2Integer and ficl2Unsigned.

Ficl 4.0 also features a retooled API, and a redesigned directory tree. The API is now far more consistent. But for those of you who are upgrading from Ficl 3.03 or before, you can enable API backwards compatibility by turning on the compile-time flag FICL_WANT_COMPATIBILITY.

Ficl 4.0 also extends support every kind of local and global value imaginable. Every values can individually be local or global, single-cell or double-cell, and integer or floating-point. And TO always does the right thing.

If you're using Ficl under Windows, you'll be happy to know that there's a brand-new build process. The Ficl build process now builds Ficl as

  • a static library (.LIB),
  • a dynamic library (.DLL, with a .LIB import library), and
  • a standalone executable (.EXE).
Furthermore, each of these targets can be built in Debug or Release, Singlethreaded or Multithreaded, and optionally using the DLL version of the C runtime library for Multithreaded builds. (And, plus, the /objects/common nonsense is gone!)

Finally, Ficl 4.0 adds a contrib directory, a repository for user-contributed code that isn't part of the standard Ficl release. The only package there right now is XClasses, a Python-based IDL that generates the definition files for C++-based classes, the equivalent Ficl classes, and code to allow the Ficl classes to call the C++ methods. Using XClasses you can write your class once, and use it immediately from both C++ and Ficl.

Getting Ficl

You can download Ficl from the Ficl download page at Sourceforge.