toylisp

Very simple and basic Lisp interpreter written in Java

Build

You need JDK 1.7+ to build toylisp.

Go to the project directory from a terminal, and type the following command to build:

./gradlew build

If you are running Windows, use the following command instead:

gradlew.bat build

If everything goes well, you will find a jar under build/libs named toylist-0.1.0-SNAPSHOT.jar.

Usage

Run the main class to get a REPL and you are free to play with it:

java -cp build/libs/toylisp-0.1.0-SNAPSHOT.jar org.toylisp.Main

Example REPL session:

toylisp> (defun double (n) (* n 2))
org.toylisp.Func@33a17727
toylisp> (map double '(0 1 2 3 4 5 6))
(0 2 4 6 8 10 12)

Data Types

Currently only three:

• Symbol
• String
• Number (implemented with Java BigDecimal)

Operations Supported

Currently only the following operators are supported:

• Special forms:
  • def Define a global variable
  • defun Define a function
  • let local binding
  • lambda Define a function
  • do Execute forms in sequence and return the value of the last expression
  • cond Conditional expression.
  • quote
  • if
• Functions: cons, car, cdr, +, -, *, /, eq?

TODO

Here is a list of features I'm planning to implement:

• core library written in toylisp itself, including but not limited to the following operations:
  • when, when-let, if-let, ->, ->> (implemented with macros)
  • mapc, mapcat, cat and other list manipulation functions
• a metacircular interpreter implemented with toylisp itself

License

Copyright © 2014 Jerry Peng

Distributed under the Eclipse Public License, the same as Clojure.