Runt

Runt is a small and quirky stack-based scripting language.

Runt can be used as a thin layer for on top of C, effecitvely making it an ideal glue language.

Here are some features:

• Stack-based: heavily inspired by Forth
• Memory-pool allocation system: only one call to malloc/free needed!
• built-in parser and interpreter, with a stack-based syntax
• written in ANSI C
• simple API for defining new words
• Can be run inside of Polysporth plugin as a scheme-extension

The source code for Runt can be found here.

Compilation

To do a full compile of Runt and the Runt Polysporth extension run:

 make

This assumes that Sporth is installed.

If you want to just compile the runt interpreter (and implicitly compile librunt):

 make irunt

To install:

 sudo make install

To clean:

 make clean

Using Runt

Starting up irunt will get you to a prompt, where you can try things out.

"Hello world" in runt looks like this:

 > "hello world!" say
 hello world!

To make procedures, record mode must be turned on, which allows you to record to the cell pool. To return to interactive mode, you must stop:

 > rec
 Recording.
 > : foo "runt is cool!" say ;
 > stop
 Stopping.
 > foo
 runt is cool!

Runt currently has supported for basic floating-point arithmetic. The "p" command pops the value from the stack and prints it.

 > 1 3 + p
 4
 > 3 2 - p
 1
 > 10 3 / p
 3.3333
 > 12345 54321 * p
 6.70593e+08

Some forth-like stack operations like swap and dup are also supported currently:

 > rec : pow dup * ; stop
 Recording.
 Stopping.
 > 5 pow p
 25

Plugins

Plugins are procedures written in C that can be dynamically loaded at runtime. They are an ideal way to "glue" other C-libraries together.

Example code for a plugin exists in plugin.c. To compile it, run:

 make plugin.so

Once it is compiled, you can start up irunt in the directory it is in, and load it into the runt cell pool:

 > "./plugin.so" dynload
 > test
 this is a plugin!

---

Projects

Home