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  3  definitions  found 
  From  Jargon  File  (4.2.3,  23  NOV  2000)  [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}.  2.  Any  of  a  number 
  of  variants  and  extensions  of  BNF  proper,  possibly  containing  some  or 
  all  of  the  {regexp}  wildcards  such  as  `*'  or  `+'.  In  fact  the  example 
  above  isn't  the  pure  form  invented  for  the  Algol-60  report;  it  uses 
  `[]',  which  was  introduced  a  few  years  later  in  IBM's  PL/I  definition 
  but  is  now  universally  recognized.  3.  In  {{science-fiction  fandom}},  a 
  `Big-Name  Fan'  (someone  famous  or  notorious).  Years  ago  a  fan  started 
  handing  out  black-on-green  BNF  buttons  at  SF  conventions;  this  confused 
  the  hacker  contingent  terribly. 
  From  The  Free  On-line  Dictionary  of  Computing  (13  Mar  01)  [foldoc]: 
  {Backus-Naur  Form}.  Originally  Backus  Normal  Form 
  [{Jargon  File}] 
  From  V.E.R.A.  --  Virtual  Entity  of  Relevant  Acronyms  13  March  2001  [vera]: 
  Backus-Naur  Form  (TTCN,  ...)