4 A hobby implementation of a forth system atop the Julia scientific
5 computing language. It will almost certainly never be useful for any
6 purpose besides that which it has already fulfilled: forcing me to
7 think quite carefully about how forth works.
9 This package owes a massive debt to the existence of the literate
10 programming project JonesForth
11 (https://rwmj.wordpress.com/2010/08/07/jonesforth-git-repository/),
12 which was an amazing read. To a large degree my package is simply a
13 port of that project from x86 assembly + forth to julia + forth,
14 although the mapping is in a few places non-trivial due to the fact
15 that julia is a high level language. During the bootstrapping
16 process, a huge proportion (say 80%) of the library code in
17 src/lib.4th was directly copied from JonesForth. (The fact that it
18 was possible to reuse this code was satisfying in its own right!)
19 Since that time I've added a significant number of core definitions
20 and modified some of the others with the eventual aim of F83
21 compliance (discussed below).
23 There's quite a lot to say about the implementation, especially due to
24 its high-level grounding, but that will have to wait for another time.
29 forth.jl is not (and probably will never be) a registered julia
30 package. To install it, you will therefore need to use the following
31 command from the Julia package manager (accessed using the `]` key):
33 (v1.0) pkg> add git://thelambdalab.xyz/forth.jl.git
35 Be aware that **forth.jl requires Julia 1.0**.
40 To start the interpreter/compiler running, simply enter the following
46 The first thing the interpreter will do is compile the core
47 definitions in the library file. Once this is complete you can start
48 entering forth commands:
53 There's an example Mandelbrot Set drawing program included in the
54 examples directory. To run it, use the `INCLUDE-LIB` word to open the
55 file and compile its definitions:
57 include-lib ../examples/mandelbrot.4th
58 Enter 'mandel' to draw the Mandelbrot Set. ok
66 *** ********************
67 ****************************** ****
68 **********************************
69 ***************************************
70 ********************************************
71 ** * *******************************************
72 ************* *********************************************
73 ****************** ********************************************
74 ******************* ********************************************
75 ** * * *******************************************************************
76 ******************* *******************************************
77 ***************** ********************************************
78 ************* ********************************************
79 ** * ********************************************
80 ********************************************
81 **************************************
82 ***********************************
83 ****************************** ****
84 ** ********************
91 (`INCLUDE-LIB` is exactly like INCLUDE, but includes files relative to
92 thte platform-dependent forth.jl src/ directory.) To exit, enter ^D on
93 a blank line or use the `BYE` word.
98 One of my goals has been to have forth.jl contain as much of the F83
100 (http://forth.sourceforge.net/standard/fst83/fst83-12.htm) as makes
101 sense given the underlying VM. (Actually, my main goal goes a bit
102 beyond this: I want to forth.jl to be, with a couple of exceptions,
103 compatible with the description of forth contained in the second
104 edition of Leo Brodie's book "Starting Forth".) I'm fairly happy with
105 my progress so far. Of the 131 required F83 words, only 20 remain
106 unimplemented. These words fall into two categories: those I may
107 possibly implement at some point, and those that I do not intend to
108 ever implement for reasons of obsolescence or incompatibility with the
111 ### F83 Words that may be implemented someday
115 These words all have to do with number to string conversion, something
116 I've not been interested in enough yet to get on top of.
118 ### F83 Words that won't be implemented
120 D+ D< DNEGATE U< UM* UM/MOD BLOCK BUFFER FLUSH
121 SAVE-BUFFERS UPDATE BLK HOLD LOAD FORTH-83
123 These words don't make sense to implement. The double-length integer
124 words are useless because the smallest unit of memory in our VM is a
125 full 64 bit integer. For the same reason, there's no point in dealing
126 with unsigned values just to gain access to another bit. The block
127 I/O words don't make sense because we have access to a filesystem via
133 This package is free software and is distributed under version 3.0 of
134 the GNU General Public License, which may be found in the file LICENSE