SNOBOL

SNOBOL 4 (String Oriented Language symbolic number 4 ) is the fourth and final expression of a number of programming languages ​​with the purpose of manipulating strings. These languages ​​were developed 1962-1967 at Bell Laboratories of AT & T by David J. Farber, Ralph E. Griswold and Ivan P. Polonsky.

The language SNOBOL 4 supports a number of built-in data types such as integer and floating point numbers, strings, patterns, fields and tables. In addition, it allows the programmer to define additional data types and new functions.

A key differentiator to the then common programming languages ​​is the existence of patterns as " first-class " data type, ie a data type whose value can be manipulated in any way as in other programming languages ​​, as well as operators for concatenation and manipulation of patterns. Character strings which are generated at run-time, can be treated as a program and executed. A pattern in SNOBOL 4 can also be very complex very easy, however. A simple pattern, for example, only a string such as " ABCD". A complex pattern, however, can be a great structure that can describe the complete grammar of a computer language for example.

In the seventies and eighties SNOBOL 4 was widely used as a language for the manipulation of texts. In recent years the popularity, however, has decreased because newer and more efficient languages ​​such as Awk and Perl have been popular for String Manipulation with regular expressions.