Scheme Registry

A catalog of the defined symbols, identifiers and other pieces of data used by Scheme standards and implementations.

Administration happens on the schemeregistry mailing list (archives, subscribe). Feel free to suggest additions and corrections there. Source is in a git repository.

Scheme standards

Registry ID: scheme-standard

ID	Name	Year
`r0rs`	Scheme: An Interpreter for Extended Lambda Calculus (AI Memo No. 349)	1975
`r1rs`	The Revised Report on Scheme (AI Memo No. 452)	1978
`r2rs`	The Revised Revised Report on Scheme (AI Memo No. 848)	1985
`r3rs`	Revised³ Report on the Algorithmic Language Scheme	1986
`ieee-1178-1990`	IEEE Standard for the Scheme Programming Language (1178-1990)	1990
`r4rs`	Revised⁴ Report on the Algorithmic Language Scheme	1991
`dsssl`	Document Style Semantics and Specification Language (ISO/IEC 10179:1996)	1996
`r5rs`	Revised⁵ Report on the Algorithmic Language Scheme	1998
`r6rs`	Revised⁶ Report on the Algorithmic Language Scheme	2007
`r7rs`	Revised⁷ Report on the Algorithmic Language Scheme (small language)	2013
`r7rs-large`	Revised⁷ Report on the Algorithmic Language Scheme (large language)

Scheme implementations

Registry ID: scheme-id

Scheme IDs for use in features, cond-expand, and many other places.

ID	Name	Contact
`airship`	Airship Scheme	Michael Babich
`bigloo`	Bigloo	Manuel Serrano
`chezscheme`	Chez Scheme	Kent Dybvig
`chibi`	Chibi-Scheme	Alex Shinn
`chicken`	CHICKEN	Felix Winkelmann
`cyclone`	Cyclone	Justin Ethier
`gambit`	Gambit Scheme	Marc Feeley
`gauche`	Gauche	Shiro Kawai
`gerbil`	Gerbil Scheme	Dimitris Vyzovitis
`guile`	GNU Guile	Andy Wingo
`ikarus`	Ikarus Scheme	Abdulaziz Ghuloum
`ironscheme`	IronScheme	Llewellyn Pritchard
`jazz`	JazzScheme	Guillaume Cartier
`kawa`	Kawa	Per Bothner
`larceny`	Larceny	William Clinger
`loko`	Loko Scheme	Göran Weinholt
`mit`	MIT Scheme	Chris Hanson
`mzscheme`	MzScheme	Matthew Flatt
`picrin`	Picrin	Yuichi Nishiwaki
`racket`	Racket	Matthew Flatt
`s7`	s7	Bill Schottstaedt
`s9fes`	Scheme 9 from Empty Space	Nils Holm
`sagittarius`	Sagittarius Scheme	Takashi Kato
`sigscheme`	SigScheme	Kazuki Ohta
`stklos`	STklos	Erick Gallesio
`unsyntax`	Unsyntax	Marc Nieper-Wißkirchen
`ypsilon`	Ypsilon	Yoshikatsu Fujita

Operating systems

Registry ID: operating-system

ID	Description
`bsd`	Operating system in BSD Unix family
`cygwin`	Cygwin Unix emulator on Windows
`darwin`	Operating system based on Darwin kernel (Apple macOS X, iOS)
`dragonfly`	DragonFly BSD operating system
`freebsd`	FreeBSD operating system
`gnu`	Operating system with GNU userland
`gnu-linux`	GNU/Linux operating system distribution
`linux`	Operating system based on Linux kernel
`macosx`	Apple MacOS X operating system (see also: darwin)
`netbsd`	NetBSD operating system
`openbsd`	OpenBSD operating system
`posix`	POSIX-compatible operating system
`solaris`	Operating system in Solaris family
`unix`	Unix-like operating system
`windows`	Operating system in Windows family

Machines

Registry ID: machine

ID	Description
`i386`	32-bit Intel/AMD x86 processor
`ppc`	PowerPC processor
`sparc`	Sun SPARC processor
`x86-64`	64-bit AMD/Intel x86 processor

Feature identifiers

Registry ID: features

ID	Description
`64bit`	Running on a 64-bit CPU (note: symbol starts with number)
`airship`	Airship Scheme
`big-endian`	The CPU byte order is big-endian
`bigloo`	Bigloo
`bsd`	Operating system in BSD Unix family
`chezscheme`	Chez Scheme
`chibi`	Chibi-Scheme
`chicken`	CHICKEN
`clang`	LLVM clang compiler [Chicken]
`clr`	Running on a Common Language Runtime (.NET CLR)
`complex`	Complex numbers are provided
`crypto`	Crypto interface [Sagittarius]
`csi`	Chicken Scheme interpreter
`cyclone`	Cyclone
`cygwin`	Cygwin Unix emulator on Windows
`darwin`	Operating system based on Darwin kernel (Apple macOS X, iOS)
`dload`	Dynamic loading of C libraries [Chicken]
`dragonfly`	DragonFly BSD operating system
`dynamic-loading`	Dynamic loading of C libraries [Chibi]
`exact-closed`	The algebraic operations +, -, *, and expt (where the second argument is a non-negative integer) produce exact values given exact inputs
`exact-complex`	Exact complex numbers are provided
`ffi`	[Sagittarius]
`ffi-vargs`	[Sagittarius]
`freebsd`	FreeBSD operating system
`full-numeric-tower`	All RnRS number types are implemented [Chicken]
`full-unicode`	All Unicode characters present in Unicode version 6.0 are supported as Scheme characters
`gambit`	Gambit Scheme
`gauche`	Gauche
`gerbil`	Gerbil Scheme
`gnu`	Operating system with GNU userland
`gnu-linux`	GNU/Linux operating system distribution
`guile`	GNU Guile
`i386`	32-bit Intel/AMD x86 processor
`ieee-float`	Inexact numbers are IEEE 754 binary floating point values
`ikarus`	Ikarus Scheme
`ilp32`	C language int, long and pointer types are all 32 bits wide
`ilp64`	C language int, long, and pointer types are all 64 its wide
`ironscheme`	IronScheme
`jazz`	JazzScheme
`jvm`	Running on a Java Virtual Machine (JVM)
`kawa`	Kawa
`larceny`	Larceny
`linux`	Operating system based on Linux kernel
`little-endian`	The CPU byte order is little-endian
`llvm`	Running on the LLVM compiler infrastructure
`loko`	Loko Scheme
`lp64`	C language int type is 32 bits, long and pointer 64 bits wide
`macosx`	Apple MacOS X operating system (see also: darwin)
`manyargs`	[Chicken]
`mit`	MIT Scheme
`mit/gnu`	MIT/GNU Scheme
`modules`	[Chibi]
`mzscheme`	MzScheme
`netbsd`	NetBSD operating system
`odbc`	ODBC interface [Sagittarius]
`openbsd`	OpenBSD operating system
`picrin`	Picrin
`posix`	POSIX-compatible operating system
`ppc`	PowerPC processor
`ptables`	[Chicken]
`r7rs`	All R7RS Scheme implementations have this feature
`racket`	Racket
`ratios`	/ with exact arguments produces an exact result when the divisor is nonzero
`regexp-backrefs`	[SRFI 115]
`regexp-look-around`	[SRFI 115]
`regexp-non-greedy`	[SRFI 115]
`regexp-unicode`	[SRFI 115]
`s7`	s7
`s9fes`	Scheme 9 from Empty Space
`sagittarius`	Sagittarius Scheme
`sigscheme`	SigScheme
`socket`	Sockets interface [Sagittarius]
`solaris`	Operating system in Solaris family
`sparc`	Sun SPARC processor
`srfi-*`	Scheme Request for Implementation number N implemented
`stklos`	STklos
`swank`	Common Lisp SWANK remote REPL protocol supported
`syntax-case`	syntax-case macros are available
`termios`	Termios interface [Sagittarius]
`threads`	Multi-threading is supported (either green threads or OS threads)
`unix`	Unix-like operating system
`unsyntax`	Unsyntax
`uvector`	[Chibi]
`windows`	Operating system in Windows family
`x86-64`	64-bit AMD/Intel x86 processor
`ypsilon`	Ypsilon
`zlib`	Zlib interface [Sagittarius]

Library name prefixes

Registry ID: library-name

ID	Description
`airship`	Airship Scheme
`bigloo`	Bigloo
`chezscheme`	Chez Scheme
`chibi`	Chibi-Scheme
`chicken`	CHICKEN
`cyclone`	Cyclone
`gambit`	Gambit Scheme
`gauche`	Gauche
`gerbil`	Gerbil Scheme
`guile`	GNU Guile
`ikarus`	Ikarus Scheme
`ironscheme`	IronScheme
`jazz`	JazzScheme
`kawa`	Kawa
`larceny`	Larceny
`loko`	Loko Scheme
`mit`	MIT Scheme
`mzscheme`	MzScheme
`picrin`	Picrin
`racket`	Racket
`rnrs`	Standard Scheme (R6RS and up)
`s7`	s7
`s9fes`	Scheme 9 from Empty Space
`sagittarius`	Sagittarius Scheme
`scheme`	Standard Scheme (R7RS and up)
`sigscheme`	SigScheme
`srfi`	Scheme Requests for Implementation
`stklos`	STklos
`unsyntax`	Unsyntax
`ypsilon`	Ypsilon

Library names under (scheme ...)

Registry ID: library-name-scheme

ID	Description
`@vector`	Homogeneous vectors [SRFI 160, R7RS Large: Tangerine Edition]
`base`	[R7RS-small]
`bitwise`	Bitwise operations [SRFI 151, R7RS Large: Tangerine Edition]
`box`	Boxes [SRFI 111, R7RS Large: Red Edition]
`bytevector`	Byte vectors [R7RS Large: Tangerine Edition]
`case-lambda`	[R7RS-small]
`char`	[R7RS-small]
`charset`	Charset library [SRFI 14, R7RS Large: Red Edition]
`comparator`	Comparators [SRFI 128, R7RS Large: Red Edition]
`complex`	[R7RS-small]
`cxr`	[R7RS-small]
`division`	Integer division [SRFI 141, R7RS Large: Tangerine Edition]
`ephemeron`	Ephemerons [SRFI 124, R7RS Large: Red Edition]
`eval`	[R7RS-small]
`flonum`	Flonums [SRFI 144, R7RS Large: Tangerine Edition]
`generator`	Generators [SRFI 158, R7RS Large: Tangerine Edition]
`generator`	Generators [SRFI 121, R7RS Large: Red Edition]
`hash-table`	Hash tables [SRFI 125, R7RS Large: Red Edition]
`ideque`	Immutable deques [SRFI 134, R7RS Large: Red Edition]
`ilist`	Immutable lists [SRFI 116, R7RS Large: Red Edition]
`inexact`	[R7RS-small]
`list`	List library [SRFI 1, R7RS Large: Red Edition]
`list-queue`	Queued-based lists [SRFI 117, R7RS Large: Red Edition]
`load`	[R7RS-small]
`lseq`	Lazy sequences [SRFI 127, R7RS Large: Red Edition]
`mapping`	Mappings [SRFI 146, R7RS Large: Tangerine Edition]
`process-context`	[R7RS-small]
`read`	[R7RS-small]
`regex`	Regular expressions [SRFI 115, R7RS Large: Tangerine Edition]
`repl`	[R7RS-small]
`rlist`	Functional, random-access pairs and lists [SRFI 101, R7RS Large: Red Edition]
`set`	Sets and bags [SRFI 113, R7RS Large: Red Edition]
`show`	Combinator Formatting [SRFI 159, R7RS Large: Tangerine Edition]
`sort`	Sort libraries [SRFI 132, R7RS Large: Red Edition]
`stream`	Streams library [SRFI 41, R7RS Large: Red Edition]
`text`	Immutable strings [SRFI 135, R7RS Large: Red Edition]
`time`	[R7RS-small]
`vector`	Vector library [SRFI 133, R7RS Large: Red Edition]
`write`	[R7RS-small]

#\ character names

Registry ID: character-name

ID	Escape	Description
`alarm`	`\a`	U+0007 [R6RS, R7RS]
`backspace`	`\b`	U+0008 [R6RS, R7RS]
`delete`		U+007F [R6RS, R7RS]
`esc`		U+001B [R6RS]
`escape`		U+001B [R7RS]
`linefeed`	`\n`	U+000A [R6RS]
`newline`	`\n`	U+000A [R6RS, R7RS]
`nul`		U+0000 [R6RS]
`null`		U+0000 [R7RS]
`page`		U+000C [R6RS]
`return`	`\r`	U+000D [R6RS, R7RS]
`space`		U+0020 [R6RS, R7RS]
`tab`	`\t`	U+0009 [R6RS, R7RS]
`vtab`		U+000B [R6RS]

# lexical syntax

Registry ID: hash-syntax

ID	Description
`#!`	Identifier follows [R6RS+]; Unix script [SRFI 22]; #! ... !# comment [Guile]
`#"..."`	Interpolated string [Gauche]
`#'`	Syntax datum [R6RS, syntax-case]
`#(...)`	Vector [R7RS]
`#*"..."`	Incomplete string [Gauche]
`#,`	unsyntax [R6RS, syntax-case]; Reader constructor [SRFI 10]
`#,@`	unsyntax-splicing [R6RS, syntax-case]
`#/.../`	Regular expression [Gauche]
`#:`	Keyword object [Chicken, Guile, S7]; Keyword marker [Kawa, Racket]; Uninterned symbol [Gauche]
`#;`	S-expression comment [R6RS, R7RS, SRFI 62]
`#<...>`	XML literal [SRFI 107]; Unreadable object [Gambit, Gauche]; import reader macro from this library [Sagittarius]
`#<<`	Multi-line string literal [Gambit]
`#<n>#`	Datum reference [R7RS]
`#<n>=`	Datum label [R7RS]
`#<n>d`	n-dimensional vector [s7]
`#<n>r`	Number in radix n [Chez Scheme]
`#?`	Debug macro [Gauche]
`#[...]`	Character set [Gauche]
`#\`	Literal character [R2RS+]
#`	quasisyntax [R6RS, syntax-case]; legacy interpolated string [Gauche]
`#a`	Array [SRFI 58, SRFI 163]
`#b`	Binary integer [R2RS+]
`#ci`	Change to case insensitive identifiers [Chicken]
`#cs`	Change to case sensitive identifiers [Chicken]
`#d`	Decimal number [R2RS+]
`#e`	Exact number [R2RS+]
`#f`	Boolean false [R3RS+]
`#false`	Boolean false [R7RS]
`#i`	Inexact number [R2RS+]; n-dimensional integer vector [s7]
`#lang`	Declare which programming language is used [Racket]
`#o`	Octal integer [R2RS+]
`#r`	n-dimensional real (i.e. float) vector [s7]
`#t`	Boolean true [R3RS+]
`#true`	Boolean true [R7RS]
`#u(...)`	n-dimensional bytevector [s7]
`#u8(...)`	Bytevector [R7RS]
`#vu8(...)`	Bytevector [R6RS]
`#x`	Hexadecimal integer [R2RS+]
`#\|...\|#`	Block comment [R6RS, R7RS, SRFI 30]

#! lexical syntax

Registry ID: hash-bang-syntax

ID	Role	Description
`bwp`	object	broken-weak-pair object [Chez Scheme]
`chezscheme`	directive	change to Chez Scheme read syntax
`compatible`	directive	R6RS+R7RS+keywords compatible syntax [Sagittarius]
`deprecated`	directive	display warning message of deprecated library [Sagittarius]
`eof`	object	end-of-file object [Chez Scheme, Chicken, Gambit, Kawa]
`err5rs`	directive	change to R7RS/R6RS syntax with extensions [Larceny]
`false`	object	the boolean value false [R2RS, archaic]
`fold-case`	directive	change to case insensitive identifiers [R7RS]
`key`	keyword	start keyword arguments in lambda list [DSSSL, SRFI 89]
`larceny`	directive	implies #!no-fold-case and #!err5rs [Larceny]
`no-fold-case`	directive	change to case sensitive identifiers [R7RS]
`no-overwrite`	directive	deny overwriting exported variables [Sagittarius]
`nocache`	directive	disable cache on the current loading file [Sagittarius]
`null`	object	the empty list [R2RS, archaic]; Java null [Kawa]
`optional`	keyword	start optional arguments in lambda list [SRFI 89]
`r5rs`	directive	change to R7RS syntax with #!fold-case [Larceny]
`r6rs`	directive	change to R6RS read syntax [R6RS]
`r7rs`	directive	change to R7RS syntax with #!no-fold-case [Gauche, Larceny, Sagittarius]
`read-macro`	directive	#!read-macro=name is the same as #<name> [Sagittarius]
`reader`	directive	#!reader=name replaces the reader with that library [Sagittarius]
`rest`	keyword	start rest argument in lambda list [SRFI 89]
`true`	object	the boolean value true [R2RS, archaic]
`void`	object	void object [Gambit, Kawa]

Filename extensions

Registry ID: filename-extension

Extension	Stands for	Description
`.scm`	Scheme	Source code for any implementation or standard
`.sps`	Scheme program source	R6RS program
`.sls`	Scheme library source	R6RS (library ...) form
`.sld`	Scheme library definition	R7RS (define-library ...) form
`.rkt`	Racket	Racket source code with #lang at the top
`.scr`	Scribe	Text document written using Scheme Scribe
`.scrbl`	Scribble	Text document written using Scribble
`.ss`	Scheme source	Equivalent to .scm
`.sc`	Scheme	Equivalent to .scm [rare]
`.sch`	Scheme	Equivalent to .scm [rare]
`.sps7`	Scheme program source	R7RS program [rare]
`.six`	Scheme infix	Scheme + infix lexical syntax [Gambit]
`.spi`	Scheme package interface	ScmPkg package definition file [Bigloo, STklos]
`.stk`	STk	Scheme code written in the STk/STklos dialect
`.ostk`	Object STk	Compiled STklos Scheme code
`.brl`	Beautiful Report Language	Text document in BRL [Kawa]
`.krl`	Kawa Report Language	Text document in KRL [Kawa]

Version flag properties

Registry ID: version-flag-property

ID	Description	Type
`build.configure`	Command line arguments to configure script	string ...
`build.date`	Date (and time) of build	iso-date-string
`build.git.branch`	Git repository state at build time - branch	string
`build.git.commit`	Git repository state at build time - commit hash	string
`build.git.modified`	Git repository state at build time - dirty files	string ...
`build.git.tag`	Git repository state at build time - tag	string
`build.platform`	OS/machine/etc. for which build was made	string
`c.compile`	C programming language compiler command	string ...
`c.link`	C programming language linker command	string ...
`c.type-bits`	C programming language data type sizes	(symbol integer) ...
`c.version`	C programming language compiler version	string
`command`	Canonical shell command name for this program	string
`encodings`	Character encodings supported by the implementation, default first	symbol ...
`image.date`	Date (and time) the Scheme image was saved	iso-date-string
`image.file`	File the Scheme image is loaded from	string
`install-dir`	Installation prefix directory (e.g. /usr/local)	string
`jvm.*`	Java system properties	string
`languages`	Programming languages supported by the implementation	symbol ...
`os.env.*`	Runtime environment variables	string
`os.stdio`	Stdin, stdout, and stderr file types	symbol symbol symbol
`os.uname`	Runtime Unix uname values	string string string
`release`	Last release version number	string
`release.date`	Last release date	iso-date-string
`release.name`	Last release codename	string
`scheme.features`	List of cond-expand features present	symbol ...
`scheme.id`	The scheme-id of this implementation	symbol
`scheme.path`	Directories to search for Scheme libraries	string ...
`scheme.srfi`	Supported SRFIs (list may not be exhaustive)	integer ...
`website`	URL of the implementation's website	string