SuperBASIC

SuperBASIC is an advanced variant of the BASIC programming language with many structured programming additions. It was developed at Sinclair Research by Jan Jones during the early 1980s. Originally SuperBASIC was intended for a home computer, code-named SuperSpectrum, then under development. This project was later cancelled, however, SuperBASIC was subsequently included in the ROM firmware of the Sinclair QL microcomputer (announced in January 1984), also serving as the command line interpreter for the QL's Qdos operating system. It is notable for being the first second-generation BASIC to be integrated into a microcomputer's operating system, so making the latter user-extendable--as exemplified by Linus Torvalds in his formative years.

The example below illustrates the last eight of these features. After entering the statements, entering

will print FRI to the screen. Until cleared (e.g. by entering NEW), the function Iso will act like an extension to the operating system. Similarly, according to the QL User Guide, "many of the operating system commands are themselves defined as procedures."

ctrl+space

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