ISO 8485:1989

ISO 8485:1989 is an international standard issued by the ISO, specifying behavior for a flat APL dialect nearly identical to APL.SV. It was succeeded by the Extended APL standard, ISO/IEC 13751:2001. The features of ISO 8485:1989 have been widely adopted, and its primitives in particular are supported by all commercial APL dialects.

Work on an APL standard was begun at IBM in 1974, shortly after the release of APL.SV. Initially, the standard was simply considered to be defined by APL.SV's implementation, but by 1977 a standard document had been written and was ratified as an IBM standard. It was published in 1979 as part of the APL79 conference proceedings, in a separate volume from the other papers for ease of reproduction. In 1987 an edited form of this standard was accepted by ISO as ISO 8485:1989.