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The Story of Mel is an archetypical piece of computer programming folklore. Its subject, Mel Kaye, is the canonical Real Programmer. == Story == Ed Nather’s ''The Story of Mel'' details the extraordinary programming prowess of a former colleague of his, "Mel", at Royal McBee Computer Corporation.〔〔Matt Crawford (The realest programmer of all ) Newsgroup: net.jokes November 20, 1984.〕 Although originally written in prose, Nather’s story was modified by someone into a "free verse" form which has become widespread.〔(The Story of Mel ) free verse version〕 Little is known about Mel Kaye, beyond the fact that he was credited with doing the "bulk of the programming" on the 1959 ACT-1 compiler for the Royal McBee LGP-30 computer.〔("New Light on the Legend of Mel" ), 1 Jun 1994, alt.folklore.computers, Bill von Hagen〕〔("In particular, Mel Kaye of Royal McBee..."'' ), FOLDOC, imperial.ac.uk〕 In Nather's story, Kaye is portrayed as being prone to avoiding optimizing assemblers in favor of crafting code to take advantage of hardware quirks, for example taking advantage of the rotation of the LGP-30's drum memory to avoid writing delay loops into the code. The story as written by Nather involved Kaye's work on rewriting a blackjack program from the LGP-30 to a newer Royal McBee system, the RPC-4000; company sales executives had requested to modify the program so that they could flip a front panel switch and cause the program to lose. Kaye reluctantly acceded to the request, but to his own delight, he got the test wrong, and the switch would instead cause the program to win every time. Subsequent to Kaye's departure, Nather was asked to fix the bug. While examining the code, he found out that an apparent infinite loop had in fact been coded in such a way as to take advantage of a carry-overflow error. Adding 1 to an instruction that decoded as "Load from address ''x''" normally yielded "Load from address ''x''+1". But when ''x'' was already the highest possible address, not only did the address wrap around to zero, but a 1 was carried into the bits from which the opcode would be read, changing the opcode from "load from" to "jump to" so that the full instruction changed from "load from the last address" to "jump to address zero". This impressed Nather so much that, out of respect, he gave up the task and reported that he could not find the bug. 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「The Story of Mel」の詳細全文を読む スポンサード リンク
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