asciigoat's core library
https://asciigoat.org/core
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38 lines
1.2 KiB
38 lines
1.2 KiB
10 years ago
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/*
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Package ebmf implements an ISO/IEC 14977
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Extended Backus–Naur Form parser, verifiers,
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and additional related helpers for AsciiGoat
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A syntax highlighter for vim and a copy of the final draft of the standard
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are included in the doc/ directory. The official standard can be downloaded from
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http://standards.iso.org/ittf/PubliclyAvailableStandards/s026153_ISO_IEC_14977_1996(E).zip
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An uberly simplified version of the EBNF grammar looks like:
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letter = "A" | "B" | "C" | "D" | "E" | "F" | "G"
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| "H" | "I" | "J" | "K" | "L" | "M" | "N"
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| "O" | "P" | "Q" | "R" | "S" | "T" | "U"
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| "V" | "W" | "X" | "Y" | "Z" ;
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digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ;
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symbol = "[" | "]" | "{" | "}" | "(" | ")" | "<" | ">"
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| "'" | '"' | "=" | "|" | "." | "," | ";" ;
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character = letter | digit | symbol | "_" ;
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identifier = letter , { letter | digit | "_" } ;
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terminal = "'" , character , { character } , "'"
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| '"' , character , { character } , '"' ;
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lhs = identifier ;
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rhs = identifier
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| terminal
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| "[" , rhs , "]"
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| "{" , rhs , "}"
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| "(" , rhs , ")"
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| rhs , "|" , rhs
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| rhs , "," , rhs ;
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rule = lhs , "=" , rhs , ";" ;
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grammar = { rule } ;
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*/
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package ebnf
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