diff options
Diffstat (limited to 'README')
| -rw-r--r-- | README | 88 |
1 files changed, 45 insertions, 43 deletions
@@ -25,83 +25,85 @@ EXTENDED DESCRIPTION (* CHARACTER CLASSES *) - _space = " " | "\n" | "\t"; - _alpha = <"a", "z"> | <"A", "Z">; - _octal = <"0", "7">; - _digit = <"0", "9">; - _xdigit = _digit | <"a", "f"> | <"A", "F">; - _nonascii = <128, 255>; + _space = " " | "\n" | "\t"; + _alpha = <"a", "z"> | <"A", "Z">; + _octal = <"0", "7">; + _digit = <"0", "9">; + _xdigit = _digit | <"a", "f"> | <"A", "F">; + _nonascii = <128, 255>; (* WHITESPACE/COMMENTS, THE GRAMMAR IS FREE-FORM *) - _comment_char = _space | !"*", !"\"", <"!", 0xFF>; - _comment_tail = [_comment_char], [_string], ("*)" | _comment_tail | -); - _comment = "(*", _comment_tail; + _comment_str_esc = "\\", (_space | <"!", 255>); + _comment_str_char = _space | !"\"", <"!", 255>; + _comment_str = "\"", {_comment_str_esc | _comment_str_char}, ("\"" | -); + _comment_char = _space | !"*)", !"\"", <"!", 0xFF>; + _comment = "(*", {_comment_char | _comment_str}, ("*)" | -); - _ = {_space | _comment}; + _ = {_space | _comment}; (* IDENTIFIERS *) - _identifier_head = _alpha | _digit | _nonascii | "_"; - _identifier_tail = _identifier_head | "-"; + _identifier_head = _alpha | _digit | _nonascii | "_"; + _identifier_tail = _identifier_head | "-"; - identifier = _identifier_head, {_identifier_tail}; + identifier = _identifier_head, {_identifier_tail}; (* STRINGS *) - _escape_simple = "\\" | "\"" | "'" | "a" | "b" | "f" | "n" | "r" | "t" | "v"; - _escape_hex = ("x" | "X"), _xdigit, _xdigit; - _escape_octal = _octal, {_octal}; (* May not exceed 255 in base 10 *) - _escape = _escape_simple | _escape_hex | _escape_octal | -; - _character = "\\", _escape | !"\"", <" ", 0xFF>; - _string = "\"", _character, {_character}, ("\"" | -); + _escape_simple = "\\" | "\"" | "'" | "a" | "b" | "f" | "n" | "r" | "t" | "v"; + _escape_hex = ("x" | "X"), _xdigit, _xdigit; + _escape_octal = _octal, {_octal}; (* May not exceed 255 in base 10 *) + _escape = _escape_simple | _escape_hex | _escape_octal | -; + _character = "\\", _escape | !"\"", <" ", 0xFF>; + _string = "\"", _character, {_character}, ("\"" | -); - string = _string - character = "\"", _character, ("\"" | -); + string = _string; + character = "\"", _character, ("\"" | -); (* INTEGERS *) - _decimal = _digit, {_digit}; - _hexadecimal = "0", ("x" | "X"), _xdigit, {_xdigit}; + _decimal = _digit, {_digit}; + _hexadecimal = "0", ("x" | "X"), _xdigit, {_xdigit}; - integer = _decimal | _hexadecimal; (* May not exceed 255. *) + integer = _hexadecimal | _decimal; (* May not exceed 255. *) (* GROUPINGS *) - _low = character | integer; - _high = character | integer; + _low = character | integer; + _high = character | integer; - nondeterministic = "?"; + nondeterministic = "?"; - committed = "+", _, _operand; - rejection = "!", _, _operand; - concatenation = _operand, {_, ",", _, _operand}; - alternation = concatenation, {_, [nondeterministic], "|", _, concatenation}; - optional = [nondeterministic], "[", _, _expression, _, "]"; - repeated = [nondeterministic], "{", _, _expression, _, "}"; - group = "(", _, _expression, _, ")"; - char-range = "<", _, _low, _, ",", _, _high, "_", ">"; - exception = "-"; - embedded-rule = identifier; + committed = "+", _, _operand; + rejection = "!", _, _operand; + concatenation = _operand, {_, ",", _, _operand}; + alternation = concatenation, {_, [nondeterministic], "|", _, concatenation}; + optional = [nondeterministic], "[", _, _expression, _, "]"; + repeated = [nondeterministic], "{", _, _expression, _, "}"; + group = "(", _, _expression, _, ")"; + char-range = "<", _, _low, _, ",", _, _high, _, ">"; + exception = "-"; + embedded-rule = identifier; - _literal = char-range | exception | string; - _group = optional | repeated | group | embedded-rule; - _operand = _group | _literal | rejection | committed; + _literal = char-range | exception | string; + _group = optional | repeated | group | embedded-rule; + _operand = _group | _literal | rejection | committed; - _expression = alternation; + _expression = alternation; (* RULES *) - rule = identifier, _, "=", _, _expression, _, ";"; + rule = identifier, _, "=", _, _expression, _, ";"; (* This is the root rule of the grammar. *) - grammar = _, {rules, _}; + grammar = _, {rule, _}; The file must be encoded in UTF-8, with LF as the line break (CR and FF are illegal just because). |