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The Jargon File, version 4.4.8 (jargon)

BNF: /B·N·F/, n. 1. [techspeak] Acronym for Backus Normal
Form (later retronymed to Backus-Naur
Form because BNF was not in fact a normal form), a metasyntactic
notation used to specify the syntax of programming languages, command sets,
and the like. Widely used for language descriptions but seldom documented
anywhere, so that it must usually be learned by osmosis from other hackers.
Consider this BNF for a U.S. postal address:This translates into English as: “A postal-address consists of
a name-part, followed by a street-address part, followed by a zip-code
part. A personal-part consists of either a first name or an initial
followed by a dot. A name-part consists of either: a personal-part
followed by a last name followed by an optional jr-part (Jr., Sr., or
dynastic number) and end-of-line, or a personal part followed by a name
part (this rule illustrates the use of recursion in BNFs, covering the case
of people who use multiple first and middle names and/or initials). A
street address consists of an optional apartment specifier, followed by a
street number, followed by a street name. A zip-part consists of a
town-name, followed by a comma, followed by a state code, followed by a
ZIP-code followed by an end-of-line.” Note that many things (such as
the format of a personal-part, apartment specifier, or ZIP-code) are left
unspecified. These are presumed to be obvious from context or detailed
somewhere nearby. See also parse.

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單詞	字典	翻譯
BNF	查看　BNF　在Google字典中的解釋	Google英翻中〔查看〕
BNF	查看　BNF　在Yahoo字典中的解釋	Yahoo英翻中〔查看〕