Qu'est-ce (qui) est SNOBOL Implementation Language - définition

PROGRAMMING LANGUAGE

SNOBOL4; SNOBOL programming language; SNOBOL 4; Snobol; SNOBOL (programming language); Vanilla SNOBOL; Snobol programming language; Snobol4; String oriented symbolic language

SNOBOL

String Oriented Symbolic Language

String Oriented Symbolic Language

<language> (SNOBOL) A string processing language for text and formula manipulation, developed by David J. Farber, Ralph E. Griswold and Ivan P. Polonsky at Bell Labs in 1962. SNOBOL had only simple control structures but provided a rich string-matching formalism of power comparable to {regular expressions} but implemented differently. People used it for simple natural language processing analysis tasks well into the 1980s. Since then, Perl has come into favour for such tasks. SNOBOL was originally called "SEXI" - String EXpression Interpreter. In spite of the suggestive name, SNOBOL is not related to COBOL. Farber said the name SNOBOL was largely contrived at the time the original JACM article was published when one of the implementors said something like, "This program doesn't have a snowball's chance in hell of ...". The expansion to "String Oriented Symbolic Language" was contrived later. Implementations include (in no particular order): SNOBOL2, SNOBOL3, SNOBOL4, FASBOL, SITBOL, MAINBOL, SPITBOL and vanilla. See also EZ, Poplar, SIL and Icon. SNOBOL 4 (http://snobol4.org/). David Farber (http://cis.upenn.edu/%7Efarber/). Ralph Griswold (http://cs.arizona.edu/people/ralph/). ["SNOBOL, A String Manipulating Language", R. Griswold et al, J ACM 11(1):21, Jan 1964]. (2004-04-29)

SNOBOL4

<language> A quite distinct descendant of SNOBOL, developed by Griswold et al in 1967. SNOBOL4 is declarative with dynamic scope. Patterns are first-class data objects that can be constructed by concatenation and alternation. Success and failure are used for flow control. Delayed (unevaluated) expressions can be used to implement recursion. It has a table data type. Strings generated at run time can be treated as programs and executed. See also vanilla. SNOBOL 4 (http://snobol4.org/). ftp://apple.com/ArchiveVol1/Unix_lang. ["The SNOBOL4 Programming Language", Ralph E. Griswold et al, P-H 1971]. (2004-04-29)

Wikipédia

SNOBOL

SNOBOL ("StriNg Oriented and symBOlic Language") is a series of programming languages developed between 1962 and 1967 at AT&T Bell Laboratories by David J. Farber, Ralph E. Griswold and Ivan P. Polonsky, culminating in SNOBOL4. It was one of a number of text-string-oriented languages developed during the 1950s and 1960s; others included COMIT and TRAC.

SNOBOL4 stands apart from most programming languages of its era by having patterns as a first-class data type (i.e. a data type whose values can be manipulated in all ways permitted to any other data type in the programming language) and by providing operators for pattern concatenation and alternation. SNOBOL4 patterns are a type of object and admit various manipulations, much like later object-oriented languages such as JavaScript whose patterns are known as regular expressions. In addition SNOBOL4 strings generated during execution can be treated as programs and either interpreted or compiled and executed (as in the eval function of other languages).

SNOBOL4 was quite widely taught in larger U.S. universities in the late 1960s and early 1970s and was widely used in the 1970s and 1980s as a text manipulation language in the humanities.

In the 1980s and 1990s, its use faded as newer languages such as AWK and Perl made string manipulation by means of regular expressions fashionable. SNOBOL4 patterns subsume BNF grammars, which are equivalent to context-free grammars and more powerful than regular expressions. The "regular expressions" in current versions of AWK and Perl are in fact extensions of regular expressions in the traditional sense, but regular expressions, unlike SNOBOL4 patterns, are not recursive, which gives a distinct computational advantage to SNOBOL4 patterns. (Recursive expressions did appear in Perl 5.10, though, released in December 2007.)

The later SL5 (1977) and Icon (1978) languages were designed by Griswold to combine the backtracking of SNOBOL4 pattern matching with more standard ALGOL-like structuring.

https://en.wikipedia.org/wiki/SNOBOL