Editing Flavors (programming language)

{{Short description|Programming language}}
{{Use American English|date=March 2021}}
{{Use mdy dates|date=March 2021}}

'''Flavors'''<ref>Howard Cannon, [http://www.softwarepreservation.org/projects/LISP/MIT/nnnfla1-20040122.pdf Flavors: A non-hierarchical approach to object-oriented programming], Symbolics Inc., 1982</ref> is an early [[object-oriented programming|object-oriented]] extension to [[Lisp programming language|Lisp]] developed by [[Howard Cannon (programmer)|Howard Cannon]] at the [[MIT Artificial Intelligence Laboratory]] for the [[Lisp machine]] and its programming language [[Lisp Machine Lisp]]. It is notable as the first programming language to include [[mixins]].<ref>pg 46 of Thompson, C. W., Ross, K. M., Tennant, H. R., and Saenz, R. M. 1983. "Building Usable Menu-Based Natural Language Interfaces To Databases". In ''Proceedings of the 9th international Conference on Very Large Data Bases'' (October 31 – November 2, 1983). M. Schkolnick and C. Thanos, Eds. Very Large Data Bases. Morgan Kaufmann Publishers, San Francisco, CA, 43–55.</ref> [[Symbolics]] used it for its Lisp machines, and eventually developed it into '''New Flavors'''; both the original and new Flavors were [[message passing|message-passing]] OO models. It was hugely influential in the development of the [[Common Lisp Object System]] (CLOS).<ref>"[[Symbolics]] (1985) was using [[New Flavors]] (a message-sending model, like Java today), Xerox was using [[CommonLoops]], [[Lisp Machine Incorporated]] was using [[Object Lisp]] (Bobrow, 1986), and [[Hewlett-Packard]] proposed using [[Common Objects]] (Kempf, 1987). The groups vied with each other in the context of the standardization effort going on for Common Lisp at the time and finally settled on a standard based on CommonLoops and New Flavors." p. 108 of Veitch 1998.</ref>

Implementations of Flavors are also available for [[Common Lisp]].<ref>[http://www.franz.com/support/documentation/10.1/doc/flavors.htm Flavors for Allegro CL]</ref>

New Flavors replaced message sending with calling [[generic function]]s.

Flavors offers {{code|:before}} and {{code|:after}} daemons with the default method combination (called {{code|:daemon}}).

== Flavors and CLOS features comparison ==
Flavors offers a few features not found in CLOS:
* Wrappers
* Automatic lexical access to slots using variables within methods.
* Internal flavor functions, macros and substs.
* Automatically generated constructors.
* {{code|DEFFLAVOR}} options: {{code|:required-methods}}, {{code|:abstract-flavor}}, {{code|:mixture}}.
* {{code|SEND}} function for sending messages.

CLOS offers the following features not found in Flavors:
* Multimethods
* Methods specialized on individual objects (via {{code|EQL}}).
* Methods specialized on Common Lisp types (symbol, integer, ...).
* Methods specialized on def-struct types.
* Class slots.

==Terminology==
{| class="wikitable"
|+ Flavors terminology
! Flavors !! CLOS
|-
| flavor || class
|-
| component flavor || superclass
|-
| dependent flavor || subclass
|-
| local component flavor || direct superclass
|-
| local dependent flavor || direct subclass
|-
| generic function || generic function
|-
| combined method || effective method
|-
| method option || method qualifier
|-
| instance || instance
|-
| instance variable || slot
|-
| ordering of flavor components || class precedence list
|}

==References==
<references/>
* {{cite book |last1=Veitch |first1=Jim |date=1998 |chapter=A History and Description of CLOS |editor-last1=Salus |editor-first1=Peter H. |editor-link1=Peter H. Salus |title=Handbook of Programming Languages, Volume IV: Functional and Logic Programming Languages |edition=1st |pages=107–158 |publisher=Macmillan Technical Publishing |isbn=1-57870-011-6}}

==Further reading==
* {{cite conference |last1=Moon |first1=David A. |author-link1=David A. Moon |date=June 1986 |title=Object-Oriented Programming with Flavors |book-title=Conference proceedings on Object-oriented Programming Systems Languages and Applications |pages=1–8 |isbn=978-0-89791-204-4 |conference=[[OOPSLA]] '86 |doi=10.1145/28697.28698 |s2cid=17150741 |url=https://www.cs.tufts.edu/comp/150FP/archive/david-moon/flavors.pdf |access-date=2022-03-17}}
* "Flavors, Technical Report", ''MIT Artificial Intelligence Laboratory'', Cambridge (Mass.), 1980
* Daniel Weinreb and [[David A. Moon]], [https://dspace.mit.edu/handle/1721.1/5700 "Flavors: Message Passing in the Lisp Machine"], A.I. Memo No. 602, November 1980, MIT AI Lab

{{Lisp programming language}}

[[Category:Lisp programming language family]]
[[Category:Common Lisp]]
[[Category:Object-oriented programming languages]]