In engineering and computer science, an implementation is the practical application of a methodology or algorithm to fulfill a desired purpose. For example, one might create a computer program that sorts a list of numbers in ascending order. To do so, one would implement a known method of sorting.
In political science, implementation refers to the carrying out of public policy. Legislatures pass laws that are then carried out by public servants working in bureaucratic agencies. This process consists of rule-making, rule- administration and rule-adjudication. Factors impacting implementation include the legislative intent, the administrative capacity of the implementing bureaucracy, interest group activity and opposition, and presidential or executive support.
See also: Interface (computer science), Java programming language.
More on [ Implementation ]
Functional :: Compilers
Compilers and Interpreters :: Lisp
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3DScheme - Two systems for Windows with built in industrial-strength solid modeler based on the ACIS solid modeler Geometric Modeling Kernel.
An Executable Denotational Semantics for Scheme - SchemeDS, as defined in R5RS. Program coded in R5RS Scheme. Description, documents, downloads. [AppSolutions Software Licensing]
Better Scheme - Language designed and largely implemented, now a matter of coding, documenting. Goals: high consistency; improve language's functional nature; consistency with lambda calculus; optimize, but not at cost of other goals.
Bigloo - System with one goal: enable Scheme-based programming style where C(++) is usually needed; makes Scheme practical via features found in most traditional languages but not Scheme and functional programming. [Open Source, GPL]
Chez Scheme - Reliable, high performance implementation, by Cadence Research Systems. Free version exists. [Commercial]
Meta Description: [ Scheme programming and Scheme language tools and documentation: Chez Scheme, Petite Chez Scheme, the Scheme Widget Library, The Scheme Programming Language, and the Chez Scheme User's Guide ]
Chicken - A Scheme compiler which compiles a subset of R5RS into C. Uses the ideas presented in Baker's paper Cheney on the MTA. It is highly portable, reasonably efficient and makes interfacing to C and C++ very easy.
CMU AI Repository Free/Shareware Scheme Implementations - Yet more Scheme implementations from the CMU AI Repository. Many of these are also available from the Indiana University Scheme Repository.
DrScheme - Full Scheme programming environment for Macintosh, many Unixes, Windows. Has module and object systems, platform-independent graphics. Ideal for beginners; one of the major design goals is a flexible teaching environment.
EdScheme - Interpreter for Macintosh or Windows. Has friendly and convenient interactive programming environment with language sensitive editor, full documentation. [commercial, free 14 day download]
Elk Scheme: The Extension Language Kit - New site. Embeddable, reusable extension language subsystem for programs coded in C/C++, also a useful standalone Scheme implementation with interfaces to POSIX, Unix, X11.
Meta Description: [ Elk Scheme - the Extension Language Kit ]
Elk: Scheme-based Extension Language Kit - Old site, last update 1997. Embeddable, reusable extension language subsystem for applications written in C/C++, also a useful standalone Scheme implementation with interfaces to POSIX, Unix, X11.
EuScheme Sources - Small implementation of Level 0 EuLisp, downloads in formats: tar, tgz, zip.
Galapagos - An interactive multithreaded Scheme interpreter with turtle graphics for Windows 95, based on SCM.
Gambit - A portable, high-performance implementation of Scheme based on an optimizing compiler by Marc Feeley. Developed at University of Montreal.
Gauche - An R5RS Scheme implementation developed to be a handy script interpreter. Quick startup, built-in system interface, native multilingual support. [Open source, BSD license]
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Hotdog - A nearly R5RS compliant Scheme compiler with multiple backends, currently including .NET, JVM, and C. [Public Domain]
Indiana University Scheme Repository: Implementations - Even more Scheme implementations freely available from the Indiana U. repository.
Infer Project - Statically-typed Scheme dialect, written in Infer, combines many of the best features of Scheme and ML. NSF funded.
Inlab Scheme - A commercial Scheme which is freely available for non-commercial use on Linux and FreeBSD. It has support for several features like bitmap/greymap processing and can be used as a general tool for image processing, OCR or specialized optical object and pattern recognition.
Meta Description: [ Inlab-Scheme is an independent implementation of the algorithmic language Scheme as defined by the R4RS and the IEEE Standard 1178. In addition to the language core Inlab-Scheme has support for several features like bitmap/greymap processing and more. ]
Kali Scheme - A distributed implementation of Scheme that permits efficient transmission of higher-order objects such as closures and continuations.
KSM-Scheme - A R5RS Scheme interpreter which integrates with C, allowing calling of C functions and accessing C variables from Scheme. It provides a mechanism to load C shared libraries. It runs on x86 and PowerPC based Linux systems.
Larceny Project - Simple, efficient Scheme run-time system, for SPARC architecture. Petit Larceny is portable and emits C, for Linux (Intel IA32), Macintosh OS X (PowerPC), Solaris (SPARC), Windows. Common Larceny runs on Microsoft Common Language Runtime (CLR), emits MS IL not native or C code.
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Lego/Scheme Compiler - For Lego MindStorms Robot kits, alternative to Visual Basic. Description, documents, downloads.
Meta Description: [ Indiana University: Computer Science Department ]
LispMe - Newer versions here. Scheme system for the Palm Pilot PDA developed by Fred Bayer.
Meta Description: [ LispMe Homepage ]
MIT Scheme - From MIT, for many systems, has comprehensive code library, includes most functionality of ANSI Standard Common Lisp (CLtL2), many low-level OS interactions. Distributed with system is LIAR (LIAR Imitates Apply Recursively), optimizing compiler that outputs native machine code, has Edwin interactive Emacs-derived editor written in pure Scheme and the subject of an MIT AI Lab Memo. Arguably one of the best Scheme systems available, unarguably one of largest. Major downfall: its not totally R5RS compliant, more so for hygienic macros and #f versus the empty list. Version 7.5 now available for x86 systems.
MzScheme - Small, embeddable, scripting PLT Scheme implementation: R5RS compliant, full numerical tower, threads (all platforms), exceptions, modules, class-based objects, regular-expression matching, TCP/IP. For Macintosh, Unix, Windows 32-bit.
Narsi - Portable scheme interpreter by Britt Park. Other free software: Cdoc, simple program to generate pretty TeX output from annotated C/C++ code. Userblock, simple user space block device driver kit for Linux. UVFS, user space filesystem kit.
Oaklisp - Object-oriented Scheme dialect with first-class types, multiple inheritance, lexically distributed method definitions. based on bytecode emulator, yet reasonably fast. Description, downloads, bibliography. [Open Source, GPL]
500
PC Scheme - Texas Instruments system for DOS OS; no longer maintained; download formats: source, executable/binary.
Petite Chez Scheme - A complete Scheme system that is fully compatible with Chez Scheme but uses high-speed threaded interpreter technology in place of Chez Scheme's incremental native-code compiler. [Freeware]
PLT Scheme - Advocacy and authoring group, umbrella name for family of implementations: DrScheme (Scheme, MzScheme, MrEd); books: How to Design Programs, How to Use Scheme; and TeachScheme! project. University-based, supported by many volunteers writing code, documentation.
Pocket Scheme - For MIPS, SH3, ARM-based Windows CE devices. Supports Aubrey Jaffer's SLIB, has initialization file for same, parenthesis-balancing text editor. Windows NT version exists. [Open Source, Artistic License]
Meta Description: [ Pocket Scheme is
a standards-compliant implementation of the Scheme programming language
for devices running the Microsoft Windows CE OS. ]
Pseudoscheme - Embeds Scheme in Common Lisp.
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QScheme - A fast, small Scheme interpreter which is mostly compliant with the R5RS standard.
500
RScheme - Portable, extended Scheme with reflective object(-oriented) system, operating system services, modules, threads, many system programming features (integrates with, compiles to C or bytecodes) and useful extensions. [Open Source]
Scheme 48 - A small and portable implementation based on a bytecode interpreter designed to be used as a testbed for experiments in implementation techniques.
Scheme 48 - Jonathan A. Rees's unofficial page: history, links, status.
Scheme 48 User's Guide - HTMLized by Margaret Fleck, one of the authors of Envision.
Scheme Implementations and Mailing Lists - A list of Scheme implementations from the Scheme FAQ maintained by Mark Kantrowitz.
Scheme-to-C - DEC's venerable translator, runs on most anything with an ANSI C compiler.
Schoca (Scheme for OCaml) - An implementation of the Scheme language in OCaml. The primary purpose of Schoca is the use as an embedded extension language in OCaml applications. [Open source, GPL]
Meta Description: [ Schoca is an implementation of the Scheme language. ]
SCM - A portable Scheme implementation written by Aubrey Jaffer.
Meta Description: [ SCM is a portable Scheme implementation conforming to
Revised^5 Report on the Algorithmic Language Scheme and the IEEE P1178
specification. ]
Scsh - Scheme Shell, broad-spectrum system programming environment for Unix, embedded in R5RS Scheme 48. Supports concurrent system programming, sophisticated I/O and automatic garbage collection for process resources.
Scsh FAQ - The FAQ for Scsh, the Scheme Shell.
Meta Description: [ Scsh Frequently Asked Questions: Table of Contents ]
SIOD: Scheme in One Defun - Very small, portable implementation, has some database, Unix programming, CGI scripting extensions. Runs on DOS, Linux, Unix, Windows. Free source downloads.
Sizzle - A Scheme interpreter implemented as a library which can be embedded into C programs, as well as a standalone interpreter. Mostly R5RS, Guile compatible, and includes regular expressions and most Posix functions.
Sketchy - Interpreter for pure functional applicative Scheme dialect, a variant of pure LISP plus global definitions (define), first-class continuations (call/cc), input/output functions (read, write, ...). Downloads: source, binaries. Sells: tutorial, reference manual.
Stalin - A powerful optimizing Scheme compiler from Jeffery Mark Siskind at the NEC Research Institute. Sacrifices functions such as call/cc in favor of efficiency, but generated code is remarkably bulletproof and fast.
STk - R4RS Scheme interpreter with interface to access Tk graphical package; can be seen as a standard Tk package with Tcl replaced by a Scheme interpreter. Has efficient CLOS-like object-oriented system, STklos.
STklos - Derived from STkn implementation based on an ad-hoc virtual machine, byte compiler; compilable as library to embed in other programs, has object system with MOP, multiple inheritance, generic functions, multimethods, module system, full R5RS tower of numbers, link to GTK+ X toolkit; almost R5RS compliant (in process), to support as many final SRFIs as possible, now supports SRFI-6.
SXM, CXEMA - Portable Scheme implementation, conforms to IEEE/ANSI standard, supports all features of R5RS Report, many features of Chez Scheme and various SRFIs. Derived from XScheme: object system dropped, many changes, additions.
T - Scheme-like language developed at Yale; is to Scheme rather as NIL is to Lisp; mainly of interest to historians and theoreticians. FTP for v3.1.
T History - Fairly detailed, by Olin Shivers.
T Project - History with: downloads, contributors, timeline, publications, influence, users, successors, Olin history errata. By Jonathan A. Rees.
T Revival Project - Scheme dialect and implementation, incompatible with R5RS, but an R3RS compatibility layer exists; to grow more compatible with R5RS over time. Description, manual, downloads, mail list, IRC, contacts, plans.
The Ksi Scheme Interpreter - Ksi is a portable, embeddable Scheme implementation written in C. Unfortunately its documentation is all in Russian at this point.
TinyScheme - Based on Mini-Scheme, tiny implementation, almost a full R5RS Scheme. Goal: embedded scripting use, but works as standalone interpreter and extensible shell tool. Recent changes reduced executable size to about 64KB on Linux/x86. [BSD]
Meta Description: [ D. Souflis, J. Shapiro - TinyScheme Download site ]
Unlikely Scheme - Small, standard-complying implementation, in C++. [Open source, zlib license]
VSCM - A portable Scheme implementation written by Matthias Blume of Princeton University. No longer actively developed.
Vx-scheme - A compact (lt;64 Kb) implementation of R4RS Scheme that compiles for VxWorks/Tornado (and is integrated with the system symbol table). [Open source, Artistic License]
Meta Description: [ An implementation of Scheme for VxWorks. ]
WinScm - Scheme environment for Windows 3.1/95; interpreter independent, though defaults to Jaffer's SCM. Used at University of Lille 1, France, for introductory programming course. Free downloads. English, Française.
XLISP - A superset of the Scheme dialect of Lisp with extensions to support object-oriented programming.
XLisp-Plus - Lisp version based on, and evolutionary improvement on, experimental XLisp.
Meta Description: [ XLISP-PLUS and links to other variants ]
XLisp-Stat - Based on XLisp, but with built-in statistics support.
Meta Description: [ Obtaining Lisp-Stat ]
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