Kalos: The tiny embeddable scripting system

Kalos is a very lightweight, easy-to-integrate scripting system for applications wanting to add easy runtime configuration and automation.

Kalos is heavily inspired by Python, though offering a more C-like syntax.

Kalos runs on everything from Arduinos to low-memory 8086 DOS all the way up to 64-bit machines!

import app;
import color;
import window;

on app.init {
    var x;
    app.fill(0, 0, window.WIDTH, window.HEIGHT, color.BLUE);
    # Draw lines every four pixels
    for x in range(0, window.WIDTH / 4) {
        app.drawline(x * 4, 0, x * 4, window.HEIGHT, color.LIGHTBLUE);
    }
    app.messagebox("Message from {app.title}", "Hello, world!");
}

Features

• Tiny VM with low system resource requirements
• Minimal C requirements: any C99-like compiler (avr-gcc and openwatcom are both supported)
• Allocation-free parser and custom allocator support for parsing and running scripts on resource-constrained devices
• Pluggable string system to build your own to support extended character sets or memory requirements
• Binary script format for pre- or external compilation in constrained applications
• Comprehensive control structures: if/else, for over iterators, loop, break/continue
• IDL-based bindings to your code with dispatch code generator
• Basic list support (improvements coming in later revisions)
• String interpolation by default
• Varargs-style invocation

Limitations

• The string system currently assumes ASCII, though it will work with UTF-8 in some cases (some functions may not work properly in the presence of multi-byte, extended UTF-8 characters).
• Lists are currently immutable and the design for mutable lists/list builders is not complete.
• Dictionaries and/or maps are not implemented.
• Objects may not be defined by script code, and object functions are not available.

Logo & Name

Logo and name thanks to 🚴🏽‍♀️@ojeda-e.

Getting Started

Read the Language Guide for tips on getting started. Check out the DOS and Arduino/AVR samples for examples of how you might get started.