https://github.com/edadma/sscheme

A small Scheme interpreter in Scala
https://github.com/edadma/sscheme

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A small Scheme interpreter in Scala

• Host: GitHub
• URL: https://github.com/edadma/sscheme
• Owner: edadma
• License: mit
• Created: 2015-04-18T21:50:20.000Z (over 9 years ago)
• Default Branch: 0.2
• Last Pushed: 2015-04-28T01:41:12.000Z (over 9 years ago)
• Last Synced: 2023-09-11T05:50:27.959Z (over 1 year ago)
• Language: Scala
• Size: 211 KB
• Stars: 0
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
SScheme

=======

SScheme is a small Scheme interpreter in Scala intended to be used as an internal DSL/scripting language.

The following is a simple example of how to use it in a Scala program. The Scheme code is from the book "The Scheme Programming Language, Third Edition" in the "Extended Examples" (section 9.2).

	import ca.hyperreal.sscheme

	object Main extends App

	{

		val env = environment(

			"""

			(define sort #f)

			(let ()

				(define dosort

					(lambda (pred? ls n)

						(if (= n 1)

							(list (car ls))

							(let ((i (quotient n 2)))

								(merge pred?

									(dosort pred? ls i)

									(dosort pred? (list-tail ls i) (- n i)))))))

				(define merge

					(lambda (pred? l1 l2)

						(cond

							((null? l1) l2)

							((null? l2) l1)

							((pred? (car l2) (car l1))

							(cons (car l2) (merge pred? l1 (cdr l2))))

							(else (cons (car l1) (merge pred? (cdr l1) l2))))))

				(set! sort

					(lambda (pred? l)

						(if (null? l) l (dosort pred? l (length l))))))

			""" )

		val l = SList( 5, 7, 3, 9, 2, 1, 6 )

		

		println( interpret( """ (sort < l) """, env add ('l -> l) ) )

		println( interpret( """ (sort > l) """, env add ('l -> l) ) )

	}

The output is:

	List(1, 2, 3, 5, 6, 7, 9)

	List(9, 7, 6, 5, 3, 2, 1)

	

## License

SScheme is distributed under the MIT License, meaning that you are free to use it in your free or proprietary software.

## Usage

Use the following elements to use SScheme in your Maven project:

	

		hyperreal

		https://dl.bintray.com/edadma/maven

	

	

		ca.hyperreal

		sscheme

		0.1

	

Add the following to your `build.sbt` file to use SScheme in your SBT project:

	resolvers += "Hyperreal Repository" at "https://dl.bintray.com/edadma/maven"

	libraryDependencies += "ca.hyperreal" %% "sscheme" % "0.1"

	

## Building

### Requirements

- SBT 13.2+

- Java 6+

Clone and build:

	git clone git://github.com/edadma/sscheme.git

	cd sscheme

	sbt assembly

This will build an executable requiring only that Java be installed.  You can now also type

	sbt run

to start the REPL, or

	sbt "run "

to execute a script.  Note that the double quotes are required.

## Executable

The latest executable can be downloaded from .