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blue wire n. [IBM] Patch wires added to circuit boards at the factory to correct design or fabrication problems. These may be necessary if there hasn't been time to design and qualify another board version. Compare purple wire, red wire, yellow wire.
blurgle /bler'gl/ n. [UK] Spoken metasyntactic variable, to indicate some text that is obvious from context, or which is already known. If several words are to be replaced, blurgle may well be doubled or tripled. "To look for something in several files use 'grep string blurgle blurgle'." In each case, "blurgle blurgle" would be understood to be replaced by the file you wished to search. Compare mumble, sense 7.
BNF /B-N-F/ n. 1. [techspeak] Acronym for 'Backus-Naur Form', a meta-syntactic 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:
63aae95d7142d91b7e908a3e5868baf1.gif 63aae95d7142d91b7e908a3e5868baf1.gif
postal-address ::= name-part street-address zip-part
63aae95d7142d91b7e908a3e5868baf1.gif 63aae95d7142d91b7e908a3e5868baf1.gif
personal-part ::= name ¦ initial "."
63aae95d7142d91b7e908a3e5868baf1.gif 63aae95d7142d91b7e908a3e5868baf1.gif
name-part ::= personal-part last-name [jr-part] EOL
63aae95d7142d91b7e908a3e5868baf1.gif¦ personal-part name-part
63aae95d7142d91b7e908a3e5868baf1.gif 63aae95d7142d91b7e908a3e5868baf1.gif
street-address ::= [apt] house-num street-name EOL
63aae95d7142d91b7e908a3e5868baf1.gif 63aae95d7142d91b7e908a3e5868baf1.gif
zip-part ::= town-name "," state-code ZIP-code EOL
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. 2. Any of a number of vari-

 
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