Editing SETL

{{Short description|Programming language}}
{{Redirect|Setl|the indigenous location in Canada|Bridge River Rapids}}
{{Infobox programming language
| logo                   = 
| paradigm               = [[Multi-paradigm programming language|multi-paradigm]]: [[Imperative programming|imperative]], [[Procedural programming|procedural]], [[Structured programming|structured]], [[Object-oriented programming|object-oriented]]
| released               = {{Start date and age|1969}}
| designer               = (Jack) [[Jacob T. Schwartz]]
| developer              = [[Courant Institute of Mathematical Sciences]]
| latest release version = 1.1
| latest release date    = {{Start date and age|2005|01|07}}
| typing                 = [[Type system#DYNAMIC|Dynamic]]
| implementations        = 
| dialects               = 
| website                = {{URL|setl.org}}
| influenced_by          = [[ALGOL 60]]
| influenced             = [[SETL2]], [[ISETL]], [[SETLX]], [[Starset (programming language)|Starset]], [[ABC (programming language)|ABC]]
}}

'''SETL''' (SET Language) is a [[very high-level programming language]]<ref name=":0">{{Cite journal |last=Schwartz |first=J. T. |last2=Dewar |first2=R. B. K. |last3=Schonberg |first3=E. |last4=Dubinsky |first4=E. |date=1986 |title=Programming with Sets |url=https://doi.org/10.1007/978-1-4613-9575-1 |journal=SpringerLink |language=en |pages=v-vii, 2, 48, 53, 57-58, 63, 113ff |doi=10.1007/978-1-4613-9575-1|url-access=subscription }}</ref> based on the mathematical [[Set theory|theory of sets]].<ref name=":2">{{Cite web |title=GNU SETL Om |url=https://setl.org/setl/doc/setl.html |access-date=2024-04-24 |website=setl.org}}</ref><ref name=":3">{{Cite news |last=Markoff |first=John |date=2009-03-04 |title=Jacob T. Schwartz, 79, Restless Scientist, Dies |url=https://www.nytimes.com/2009/03/04/science/04schwartz.html |access-date=2024-04-24 |work=The New York Times |language=en-US |issn=0362-4331}}</ref> It was originally developed at the [[New York University]] (NYU) [[Courant Institute of Mathematical Sciences]] in the late 1960s, by a group containing (Jack) [[Jacob T. Schwartz]],<ref name=":0" /><ref name=":3" /> R.B.K. Dewar, and E. Schonberg.<ref name=":0" /> Schwartz is credited with designing the language.<ref>{{Cite book |url=https://link.springer.com/book/10.1007/978-0-85729-808-9 |title=Computational Logic and Set Theory |pages=vii |language=en |doi=10.1007/978-0-85729-808-9}}</ref>

== Design ==
SETL provides two basic aggregate data types: (unordered) ''sets'', and ''tuples''.<ref name=":0" /><ref name=":2" /><ref name=":4">{{Cite web |title=CHAPTER 2 |url=https://www.settheory.com/Chapters/Chapter_2.html |access-date=2024-04-24 |website=www.settheory.com}}</ref> The elements of sets and tuples can be of any arbitrary type, including sets and tuples themselves, except the undefined value '''om'''<ref name=":0" /> (sometimes capitalized: '''OM''').<ref>{{Cite web |title=CHAPTER 3 |url=https://www.settheory.com/Chapters/Chapter_3.html |access-date=2024-04-24 |website=www.settheory.com}}</ref> ''Maps'' are provided as sets of ''pairs'' (i.e., tuples of length 2) and can have arbitrary domain and range types.<ref name=":0" /><ref name=":4" /> Primitive operations in SETL include set membership, union, intersection, and power set construction, among others.<ref name=":0" /><ref name=":5">{{Cite web |title=CHAPTER 3 |url=https://www.settheory.com/Chapters/Chapter_3.html |access-date=2024-04-24 |website=www.settheory.com}}</ref>

SETL provides quantified boolean expressions constructed using the [[universal quantifier|universal]] and [[existential quantifier]]s of [[first-order predicate logic]].<ref name=":0" /><ref name=":5" />

SETL provides several [[iterator]]s to produce a variety of loops over aggregate data structures.<ref name=":0" /><ref>{{Cite web |title=CHAPTER 4 |url=https://www.settheory.com/Chapters/Chapter_4.html |access-date=2024-04-24 |website=www.settheory.com}}</ref>

== Examples ==
Print all prime numbers from 2 to {{Var|N}}:
 print([n in [2..N] | forall m in {2..n - 1} | n mod m > 0]);
The notation is similar to [[list comprehension]].

A factorial procedure definition:
 procedure factorial(n); -- calculates the factorial n!
   return if n = 1 then 1 else n * factorial(n - 1) end if;
 end factorial;

A more conventional SETL expression for factorial (n > 0):
 */[1..n]

== Uses ==
Implementations of SETL were available on the [[CDC 6600]], [[CDC Cyber]], DEC [[VAX]], [[IBM/370]], [[Sun Microsystems|SUN]] workstation and [[Apollo Computer|APOLLO]].<ref>{{cite book
 | title = Programming with sets. An Introduction to SETL
 | author = J.T. Schwartz
 | author2 = R.B.K. Dewar
 | author3 = E. Dubinsky
 | author4 = E. Schonberg
 | publisher = Springer-Verlag New York Inc.
 | year = 1986
 | isbn = 978-1-4613-9577-5
 | url = https://books.google.com/books?id=4pfbBwAAQBAJ&pg=PR6
}}</ref>
In the 1970s, SETL was ported to the [[BESM-6]], [[ES EVM]] and other Russian computer systems.<ref>{{cite book
 | title = Становление новосибирской школы программирования (мозаика воспоминаний)
 | trans-title = Formation of the Novosibirsk school of programming (mosaic of memories)
 | editor = И.В. Поттосин
 | location = Новосибирск
 | publisher = Институт систем информатики им. А. П. Ершова СО РАН
 | year = 2001
 | pages = 106–113
 | url = https://www.iis.nsk.su/files/articles/mozaika.pdf
 | language = ru
}}</ref>

SETL was used for an early implementation of the programming language [[Ada (programming language)|Ada]], named the NYU Ada/ED translator.<ref>{{cite book |first1=Robert B. K. |last1=Dewar |first2=Gerald A. |last2=Fisher Jr. |first3=Edmond |last3=Schonberg |first4=Robert |last4=Froelich |first5=Stephen |last5=Bryant |first6=Clinton F. |last6=Goss |first7=Michael |last7=Burke |title=Proceeding of the ACM-SIGPLAN symposium on Ada programming language - SIGPLAN '80 |chapter=The NYU Ada translator and interpreter |volume=15 |issue=11 |pages=194–201 |date=November 1980 |isbn=0-89791-030-3 |doi=10.1145/948632.948659|s2cid=10586359 }}</ref> This later became the first validated Ada implementation, certified on April 11, 1983.<ref>{{cite web |url=http://www.dtic.mil/docs/citations/ADA136759 |archive-url=https://web.archive.org/web/20170607044753/http://www.dtic.mil/docs/citations/ADA136759 |url-status=dead |archive-date=June 7, 2017 |title=Ada Compiler Validation Summary Report: NYU Ada/ED, Version 19.7 V-001 |author=SofTech Inc., Waltham, MA |date=1983-04-11 |access-date=2010-12-16}}</ref>

According to [[Guido van Rossum]], "[[Python (programming language)|Python]]'s predecessor, [[ABC (programming language)|ABC]], was inspired by SETL -- [[Lambert Meertens]] spent a year with the SETL group at NYU before coming up with the final ABC design!"<ref>[http://mail.python.org/pipermail/python-dev/2000-August/008881.html Python-Dev: SETL (was: Lukewarm about range literals)]</ref>

==Language variants==
''SET Language 2'' (SETL2), a backward incompatible descendant of SETL, was created by Kirk Snyder of the Courant Institute of Mathematical Sciences at [[New York University]] in the late 1980s.<ref name=":1">{{Cite web |title=SETL2 - EDM2 |url=http://www.edm2.com/index.php/SETL2 |access-date=2024-04-24 |website=www.edm2.com}}</ref> Like its predecessor, it is based on the theory and notation of finite sets, but has also been influenced in syntax and style by the Ada language.<ref name=":1" />

''Interactive SET Language'' (ISETL) is a variant of SETL used in [[discrete mathematics]].<ref>{{Cite book |last=Baxter Hastings |first=Nancy |title=Learning discrete mathematics with ISETL |last2=Dubinsky |first2=Ed |last3=Levin |first3=Gary |date=1989 |publisher=Springer-Verlag |isbn=978-0-387-96898-8 |location=New York}}</ref>

''GNU SETL'' is a command-line utility that extends and implements SETL.<ref>{{Cite web |title=GNU SETL |url=https://setl.org/setl/ |access-date=2024-04-24 |website=setl.org}}</ref>

== References ==
{{Reflist}}

== Further reading ==
* Schwartz, Jacob T., "Set Theory as a Language for Program Specification and Programming". Courant Institute of Mathematical Sciences, New York University, 1970.
* Schwartz, Jacob T., "On Programming, An Interim Report on the SETL Project", Computer Science Department, Courant Institute of Mathematical Sciences, New York University (1973).
* Schwartz, Jacob T., Dewar, R.B.K., Dubinsky, E., and Schonberg, E., ''Programming With Sets: An Introduction to SETL'', 1986. {{ISBN|0-387-96399-5}}.

== External links ==
* {{Official website}}
* [http://www.settheory.com ''Programming in SETL'' and other things]
* [http://www.softwarepreservation.org/projects/SETL SETL Historical Sources Archive]

{{Authority control}}

[[Category:Academic programming languages]]
[[Category:Set theoretic programming languages]]
[[Category:Programming languages created in 1969]]