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Applesoft BASIC is a dialect of Microsoft BASIC, developed by Marc McDonald and Ric Weiland, supplied with the Apple II series of computers. It supersedes Integer BASIC and is the BASIC in ROM in all Apple II series computers after the original Apple II model. It is also referred to as FP BASIC (from "floating point") because of the Disk Operating System (DOS) command used to invoke it, instead of INT for Integer BASIC. Applesoft BASIC was supplied by Microsoft and its name is derived from the names of both Apple and Microsoft. Apple employees, including Randy Wigginton, adapted Microsoft's interpreter for the Apple II and added several features. The first version of Applesoft was released in 1977 only on cassette tape and lacked proper support for high-resolution graphics. Applesoft II, which was made available on cassette and disk and in the ROM of the Apple II Plus and subsequent models, was released in 1978. It is this latter version, which has some syntax differences from the first as well as support for the Apple II high-resolution graphics modes, that most people mean by the term "Applesoft." ==Background== When Steve Wozniak wrote Integer BASIC for the Apple II, he did not implement support for floating point math because he was primarily interested in writing games, a task for which integers alone were sufficient. In 1976, Microsoft had developed Microsoft BASIC, a BASIC interpreter for the MOS Technology 6502, but at the time there was no production computer that used it. Upon learning that Apple had a 6502 machine, Microsoft asked if the company were interested in licensing BASIC, but Steve Jobs replied that Apple already had one. The Apple II was unveiled to the public at the West Coast Consumer Electronics Expo in April 1977 and became available for sale in June. One of the most common customer complaints about the computer was BASIC's lack of floating-point capability. Integer BASIC is limited to whole numbers between −32768 and 32767 and caused problems for users attempting to write business applications with it. As Wozniak—the only person who understood Integer BASIC well enough to add floating point features—was busy with the Disk II drive and controller and with Apple DOS, Apple turned to Microsoft. Apple reportedly obtained an eight-year license for Applesoft BASIC from Microsoft for a flat fee of $21,000, renewing it in 1985 through an arrangement that gave Microsoft the rights and source code for Apple's Macintosh version of BASIC.〔Herzfeld, Andy "MacBasic – The Sad Story of MacBasic". http://www.folklore.org/StoryView.py?project=Macintosh&story=MacBasic.txt . Folklore.org. 2014 February 12〕 Applesoft was designed to be backwards-compatible with Integer BASIC and uses the core of Microsoft's 6502 BASIC implementation, which includes using the GET command for detecting key presses and not requiring any spaces on program lines. While Applesoft BASIC is slower than Integer BASIC, it has many features that the older BASIC lacks: * Atomic strings: A string is no longer an array of characters (as in Integer BASIC and C); it is instead a garbage-collected object (as in Scheme and Java). This allows for string arrays; DIM A$(10) resulted in a vector of ''eleven'' string variables numbered 0–10.* Multidimensional arrays (numbers or strings) * Single-precision floating point variables with an 8-bit exponent and a 31-bit significand and improved math capabilities, including trigonometry and logarithmic functions * Commands for high-resolution graphics * DATA statements, with READ and RESTORE commands, for representing numerical and string values in quantity* CHR$, STR$, and VAL functions for converting between string and numeric types (both languages did have the ASC function)* User-defined functions: simple one-line functions written in BASIC, with a single parameter * Error-trapping, allowing BASIC programs to handle unexpected errors by means of a subroutine written in BASIC Conversely, Applesoft lacked the MOD (remainder) operator that had been present in Integer BASIC.Microsoft licensed a BASIC compatible with Applesoft to VTech for its Laser 128 clone. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Applesoft BASIC」の詳細全文を読む スポンサード リンク
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