Smalltalk
verb (used without object)
1.
to engage in or have a propensity for small talk.
language
The pioneering object-oriented programming system developed in 1972 by the Software Concepts Group, led by Alan Kay, at Xerox PARC between 1971 and 1983. It includes a language, a programming environment, and an extensive object library.
Smalltalk took the concepts of class and message from Simula-67 and made them all-pervasive. Innovations included the bitmap display, windowing system, and use of a mouse.
The syntax is very simple. The fundamental construction is to send a message to an object:
object message
or with extra parameters
object message: param1 secondArg: param2 .. nthArg: paramN
where “secondArg:” etc. are considered to be part of the message name.
Five pseudo-variables are defined: “self”, “super”, “nil”, “true”, “false”. “self” is the receiver of the current message. “super” is used to delegate processing of a message to the superclass of the receiver. “nil” is a reference to “nothing” (an instance of UndefinedObject). All variables initially contain a reference to nil. “true” and “false” are Booleans.
In Smalltalk, any message can be sent to any object. The recipient object itself decides (based on the message name, also called the “message selector”) how to respond to the message. Because of that, the multiple inheritance system included in the early versions of Smalltalk-80 appeared to be unused in practice. All modern implementations have single inheritance, so each class can have at most one superclass.
Early implementations were interpreted but all modern ones use dynamic translation (JIT).
Early versions were Smalltalk-72, Smalltalk-74, Smalltalk-76 (inheritance taken from Simula, and concurrency), and Smalltalk-78, Smalltalk-80. Other versions include Little Smalltalk, Smalltalk/V, Kamin’s interpreters. Current versions are VisualWorks, Squeak, VisualAge, Dolphin Smalltalk, Object Studio, GNU Smalltalk.
See also: International Smalltalk Association.
UIUC Smalltalk archive (http://st-www.cs.uiuc.edu/). FAQ (http://XCF.Berkeley.EDU/pub/misc/smalltalk/FAQ/).
Usenet newsgroup: news:comp.lang.smalltalk.
[“The Smalltalk-76 Programming System Design and Implementation”, D.H. Ingalls, 5th POPL, ACM 1978, pp. 9-16].
(2001-09-11)
Read Also:
- Small-talk
verb (used without object) 1. to engage in or have a propensity for small talk. noun 1. light conversation; chitchat. noun 1. light conversation for social occasions small potatoes Casual or trivial conversation, chitchat, as in We stood around making small talk until the guest of honor arrived. The small in this expression alludes to […]
- Smalltalk-80
language The classic standard Smalltalk dialect, described in Adele’s book, cited below, commonly known as “The Blue Book”. [“Smalltalk-80: The Language and Its Implementation”, Adele Goldberg et al, A-W 1983]. [BYTE 6(8), Aug 1981]. (ftp://st.cs.uiuc.edu/pub/ISA), (ftp://st.cs.uiuc.edu/pub/Smalltalk/MANCHESTER), (ftp://gnu.org/pub/gnu). Mail server: [email protected]. (2004-12-14)
- Small-time
adjective 1. of modest or insignificant size, importance, or influence: a small-time politician. noun, (in vaudeville) 1. a circuit of minor theaters giving three or more shows daily. adjective 1. (informal) insignificant; minor: a small-time criminal small print, the A modest or minor level of achievement, as in Her success took her out of the […]
- Small-town
adjective 1. of, relating to, or characteristic of a town or village: a typical, small-town general store. 2. provincial or unsophisticated: small-town manners.
- Smallvdm
tool [“SmallVDM: An Environment for Formal Specification and Prototyping in Smalltalk”, in Object Oriented Specification Case Studies, K. Lano et al eds, P-H 1993]. (1996-04-20)