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ebnf: replace ebnf.ebnf with grammar from the iso 14977

Signed-off-by: Alejandro Mery <amery@geeks.cl>
v0.2.x
Alejandro Mery 10 years ago
parent
commit
2991b67b39
  1. 253
      ebnf/ebnf.ebnf

253
ebnf/ebnf.ebnf

@ -1,25 +1,230 @@
(* vim: set ft=ebnf: *) (* vim: set ft=ebnf: *)
letter = "A" | "B" | "C" | "D" | "E" | "F" | "G"
| "H" | "I" | "J" | "K" | "L" | "M" | "N" (*
| "O" | "P" | "Q" | "R" | "S" | "T" | "U" The syntax of Extended BNF can be defined using
| "V" | "W" | "X" | "Y" | "Z" ; itself. There are four parts in this example,
digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ; the first part names the characters, the second
symbol = "[" | "]" | "{" | "}" | "(" | ")" | "<" | ">" part defines the removal of unnecessary non-
| "'" | '"' | "=" | "|" | "." | "," | ";" ; printing characters, the third part defines the
character = letter | digit | symbol | "_" ; removal of textual comments, and the final part
defines the structure of Extended BNF itself.
identifier = letter , { letter | digit | "_" } ;
terminal = "'" , character , { character } , "'" Each syntax rule in this example starts with a
| '"' , character , { character } , '"' ; comment that identifies the corresponding clause
in the standard.
lhs = identifier ;
rhs = identifier The meaning of special-sequences is not defined
| terminal in the standard. In this example (see the
| "[" , rhs , "]" reference to 7.6) they represent control
| "{" , rhs , "}" functions defined by ISO/IEC 6429:1992.
| "(" , rhs , ")" Another special-sequence defines a
| rhs , "|" , rhs syntactic-exception (see the reference to 4.7).
| rhs , "," , rhs ; *)
rule = lhs , "=" , rhs , ";" ; (*
grammar = { rule } ; The first part of the lexical syntax defines the
characters in the 7-bit character set (ISO/IEC
646:1991) that represent each terminal-character
and gap-separator in Extended BNF.
*)
(* see 7.2 *) letter
= 'a' | 'b' | 'c' | 'd' | 'e' | 'f' | 'g' | 'h'
| 'i' | 'j' | 'k' | 'l' | 'm' | 'n' | 'o' | 'p'
| 'q' | 'r' | 's' | 't' | 'u' | 'v' | 'w' | 'x'
| 'y' | 'z'
| 'A' | 'B' | 'C' | 'D' | 'E' | 'F' | 'G' | 'H'
| 'I' | 'J' | 'K' | 'L' | 'M' | 'N' | 'O' | 'P'
| 'Q' | 'R' | 'S' | 'T' | 'U' | 'V' | 'W' | 'X'
| 'Y' | 'Z';
(* see 7.2 *) decimal digit
= '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7'
| '8' | '9';
(*
The representation of the following
terminal-characters is defined in clauses 7.3,
7.4 and tables 1, 2.
*)
concatenate symbol = ',';
defining symbol = '=';
definition separator symbol = '|' | '/' | '!';
end comment symbol = '*)';
end group symbol = ')';
end option symbol = ']' | '/)';
end repeat symbol = '}' | ':)';
except symbol = '-';
first quote symbol = "'";
repetition symbol = '*';
second quote symbol = '"';
special sequence symbol = '?';
start comment symbol = '(*';
start group symbol = '(';
start option symbol = '[' | '(/';
start repeat symbol = '{' | '(:';
terminator symbol = ';' | '.';
(* see 7.5 *) other character
= ' ' | ':' | '+' | '_' | '%' | 'Q'
| '&' | '#' | '$' | '<' | '>' | '\'
| 'ˆ' | '' | ' ̃';
(* see 7.6 *) space character = ' ';
horizontal tabulation character
= ? ISO 6429 character Horizontal Tabulation ? ;
new line
= { ? ISO 6429 character Carriage Return ? },
? ISO 6429 character Line Feed ?,
{ ? ISO 6429 character Carriage Return ? };
vertical tabulation character
= ? ISO 6429 character Vertical Tabulation ? ;
form feed
= ? ISO 6429 character Form Feed ? ;
(*
The second part of the syntax defines the
removal of unnecessary non-printing characters
from a syntax.
*)
(* see 6.2 *) terminal character
= letter
| decimal digit
| concatenate symbol
| defining symbol
| definition separator symbol
| end comment symbol
| end group symbol
| end option symbol
| end repeat symbol
| except symbol
| first quote symbol
| repetition symbol
| second quote symbol
| special sequence symbol
| start comment symbol
| start group symbol
| start option symbol
| start repeat symbol
| terminator symbol
| other character;
(* see 6.3 *) gap free symbol
= terminal character
- (first quote symbol | second quote symbol)
| terminal string;
(* see 4.16 *) terminal string
= first quote symbol, first terminal character,
{first terminal character},
first quote symbol
| second quote symbol, second terminal character,
{second terminal character},
second quote symbol;
(* see 4.17 *) first terminal character
= terminal character - first quote symbol;
(* see 4.18 *) second terminal character
= terminal character - second quote symbol;
(* see 6.4 *) gap separator
= space character
| horizontal tabulation character
| new line
| vertical tabulation character
| form feed;
(* see 6.5 *) syntax
= {gap separator},
gap free symbol, {gap separator},
{gap free symbol, {gap separator}};
(*
The third part of the syntax defines the
removal of bracketed-textual-comments from
gap-free-symbols that form a syntax.
*)
(* see 6.6 *) commentless symbol
= terminal character
- (letter
| decimal digit
| first quote symbol
| second quote symbol
| start comment symbol
| end comment symbol
| special sequence symbol
| other character)
| meta identifier
| integer
| terminal string
| special sequence;
(* see 4.9 *) integer
= decimal digit, {decimal digit};
(* see 4.14 *) meta identifier
= letter, {meta identifier character};
(* see 4.15 *) meta identifier character
= letter
| decimal digit;
(* see 4.19 *) special sequence
= special sequence symbol,
{special sequence character},
special sequence symbol;
(* see 4.20 *) special sequence character
= terminal character - special sequence symbol;
(* see 6.7 *) comment symbol
= bracketed textual comment
| other character
| commentless symbol;
(* see 6.8 *) bracketed textual comment
= start comment symbol, {comment symbol},
end comment symbol;
(* see 6.9 *) syntax
= {bracketed textual comment},
commentless symbol,
{bracketed textual comment},
{commentless symbol,
{bracketed textual comment}};
(*
The final part of the syntax defines the
abstract syntax of Extended BNF, i.e. the
structure in terms of the commentless symbols.
*)
(* see 4.2 *) syntax
= syntax rule, {syntax rule};
(* see 4.3 *) syntax rule
= meta identifier, defining symbol,
definitions list, terminator symbol;
(* see 4.4 *) definitions list
= single definition,
{definition separator symbol,
single definition};
(* see 4.5 *) single definition
= syntactic term,
{concatenate symbol, syntactic term};
(* see 4.6 *) syntactic term
= syntactic factor,
[except symbol, syntactic exception];
(* see 4.7 *) syntactic exception
= ? a syntactic-factor that could be replaced
by a syntactic-factor containing no
meta-identifiers
? ;
(* see 4.8 *) syntactic factor
= [integer, repetition symbol],
syntactic primary;
(* see 4.10 *) syntactic primary
= optional sequence
| repeated sequence
| grouped sequence
| meta identifier
| terminal string
| special sequence
| empty sequence;
(* see 4.11 *) optional sequence
= start option symbol, definitions list,
end option symbol;
(* see 4.12 *) repeated sequence
= start repeat symbol, definitions list,
end repeat symbol;
(* see 4.13 *) grouped sequence
= start group symbol, definitions list,
end group symbol;
(* see 4.21 *) empty sequence
= ;

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