Coy - Not Quite Joy

Coy is a programming language very similar to Joy.

This project was originally intended to be an implementation of Joy in Scheme. However, some details proved difficult to match exactly, and I am not entirely sure of my interpretation of the Joy documentation. It seemed safer to choose another name and not to claim that this is actually Joy.

Status: Experimental. This program has no release number.

Getting Started

First, download Coy and unpack it. It requires an R⁵RS Scheme interpreter. The included shell script works if you have Gauche installed.

If you want to run Coy from Scheme, you must load coy.scm and call the coy function. To leave the Coy interpreter, type an EOF character (Ctrl-D) or run Coy's quit function.

Features

• trace and untrace - These functions will let you watch the contents of the data stack and the remaining program words as your programs execute. They have no stack effects.
• call/cc - This function pops a quotation q, pushes the current continuation as a quotation, then executes q.

Changes

June 26, 2005:

• Posted this web page to advertise Coy's existence.

April 26, 2005:

• A parser exists for Coy's metalanguage.
• The user can DEFINE new words.
• About 80% of Joy's standard words are implemented.
• Very little testing has been done.

April 15, 2005:

• Began work on Coy interpreter.
• Uses Scheme's read function for input.
• About 50% of Joy's standard words are implemented.