SIOD

Scheme In One Defun, or humorously Scheme In One Day (SIOD) is a programming language, a dialect of the language Lisp, a small-size implementation of the dialect Scheme, written in C and designed to be embedded inside C programs. It is notable for being perhaps the smallest practical implementation of a Lisp-like language. It was written by George J. Carrette originally. It is free and open-source software released under a GNU Lesser General Public License (LGPL).

SIOD

Paradigms	Multi: functional, procedural, meta
Family	Lisp
Designed by	George J. Carrette
Developer	George J. Carrette
First appeared	April 1988; 37 years ago (1988-04)
Stable release	3.63 / 27 April 2008; 17 years ago (2008-04-27)
Typing discipline	Strong, dynamic, latent
Scope	Lexical
Implementation language	C
Platform	VAX, SPARC, IA-32
OS	Cross-platform: Linux, Solaris, IRIX, OpenVMS, Windows
License	LGPL
Website	people.delphiforums.com/gjc//siod.html
Influenced by
Lisp, Scheme
Influenced
SCM, Guile

Features

SIOD features include:

• Implements the original version of Scheme from the Lambda Papers, but none of the modern language standards.
• Represents a very early use of conservative garbage collection in a Lisp interpreter, a method later copied by SCM and Guile.
• Compiling is implemented by emitting a fixed machine code prologue followed by a fast-loading binary representation of the parse tree to be interpreted.

Applications

• GNU Image Manipulation Program (GIMP) – SIOD was its primary extension language, Script-Fu, until GIMP 2.4 was released.^[1]
• Siag Office – Scheme in a Grid (SIAG) is a spreadsheet application using SIOD as a base.
• Festival Speech Synthesis System – SIOD is its underlying command interpreter.^[2]