ASIM

A Stack Intensive Machine, A SImple Machine, Algorithm SIMulator = = = =

ASIM is a simple runtime environment that implements a stack based machine. The runtime includes an embedded interpreter which uses reverse polish notation to put items on the stack and execute them.
The thing is written in LuaJIT, which is compiled to a self contained executable. The operator keywords, and program constructs derive from the Postscript language. As such, referring to Postscript documentation will be helpful in understanding how the environment operates.

The base runtime does not include the graphics operators that are in the Postscript language, but it includes most other operators, including the file operators. The lj2ps contains robust support for Postscript graphics, using blend2d as a vector graphics backend.

Getting Started

At present, the /build directory contains a binary for Windows asim.exe. Download this and put it somewhere accessbile from the command line. There are no other dependencies or libraries, startup files and the like to be concerned with.

Building your own

You can build this yourself, assuming you have an instance of luajit already on your machine. The build directory has a 'msvcbuild.bat' file. Simply call this from the command line and you'll be left with your own copy of asm.exe. The included lua51.lib is built for 64-bit applications, so if you want 32-bit, simply replace this with a 32-bit version and you're good to go.

Execute your first program

To execute, simply call asim.exe and you'll see a prompt

asim
==>

From there, you can start trying out simple commands.

==> 1 2 add ==
3

Exiting the runtime

Ctl-C a couple of times, and you're back to the Windows command prompt

Running a program in a file

Typing single lines of code interactively in the interpreter can bring only so much joy to your life. Things are much more fun when you can write more extensive multi-line programs.

From the interactive prompt, you can execute code from a file using the 'run' operator. So, if you typed the following into a file (ex1.ap):

%!PS
% usage: 
%   asim 
%   ==> (ex1.ap) run
%
1 2 add
pstack
3 mul
sqrt
==

You could then run it with:

==> (ex1.ap) run

Never mind what this particular program does, this is the general way to execute programs that are inside files. The name of the file does not matter. There is no meaning to the '.ap' extension, I just felt like having some extension.

Documentation

The documentation should give you a good idea of the runtime and how the various operators work. You can also find some examples within the examples directory of the repository.

Note

Postscript is a registered trademark of Adobe Systems Incorporated. The copyright to the Postscript language is also held by Adobe Systems Incorporated. This site is not relate to, supported by, or in any way condoned by Adobe in any way.

LICENSE

<a rel="license" href="http://creativecommons.org/licenses/by-sa/4.0/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by-sa/4.0/88x31.png" /></a><br />This work is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by-sa/4.0/">Creative Commons Attribution-ShareAlike 4.0 International License</a>.