BASIC

language Beginner's All-purpose Symbolic Instruction Code.

A simple language oroginally designed for ease of programming

by students and beginners.

BASIC exists in many dialects, and is popular on

microcomputers with sound and graphics support. Most micro

versions are interactive and interpreted.

BASIC has become the leading cause of brain-damage in

proto-hackers. This is another case (like Pascal) of the

cascading lossage that happens when a language deliberately

designed as an educational toy gets taken too seriously. A

novice can write short BASIC programs (on the order of 10-20

lines) very easily; writing anything longer is (a) very

painful, and (b) encourages bad habits that will make it

harder to use more powerful languages well. This wouldn't be

so bad if historical accidents hadn't made BASIC so common on

low-end micros. As it is, it ruins thousands of potential

wizards a year.

Originally, all references to code, both GOTO and GOSUB

(subroutine call) referred to the destination by its line

number. This allowed for very simple editing in the days

before text editors were considered essential. Just typing

the line number deleted the line and to edit a line you just

typed the new line with the same number. Programs were

typically numbered in steps of ten to allow for insertions.

Later versions, such as BASIC V, allow GOTO-less

structured programming with named procedures and

functions, IF-THEN-ELSE-ENDIF constructs and WHILE loops

etc.

Early BASICs had no graphic operations except with graphic

characters. In the 1970s BASIC interpreters became standard

features in mainframes and minicomputers. Some versions

included matrix operations as language primitives.

A public domain interpreter for a mixture of DEC's

MU-Basic and Microsoft Basic is here.

A yacc parser and interpreter were in the

comp.sources.unix archives volume 2.

See also ANSI Minimal BASIC, bournebasic, bwBASIC,

ubasic, Visual Basic.

[Jargon File]

(1995-03-15)