diff options
Diffstat (limited to 'context/data/textadept/context/lexers/scite-context-lexer-bnf.lua')
| -rw-r--r-- | context/data/textadept/context/lexers/scite-context-lexer-bnf.lua | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/context/data/textadept/context/lexers/scite-context-lexer-bnf.lua b/context/data/textadept/context/lexers/scite-context-lexer-bnf.lua new file mode 100644 index 000000000..ce57642ba --- /dev/null +++ b/context/data/textadept/context/lexers/scite-context-lexer-bnf.lua @@ -0,0 +1,99 @@ +local info = { + version = 1.001, + comment = "scintilla lpeg lexer for bnf", + author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "see context related readme files", +} + +-- will replace the one in metafun + +local global, lpeg = _G, lpeg +local P, R, S = lpeg.P, lpeg.R, lpeg.S + +local lexer = require("scite-context-lexer") +local context = lexer.context +local patterns = context.patterns + +local token = lexer.token +local exact_match = lexer.exact_match + +local bnflexer = lexer.new("bnf","scite-context-lexer-bnf") +local whitespace = bnflexer.whitespace + +-- from wikipedia: +-- +-- <syntax> ::= <rule> | <rule> <syntax> +-- <rule> ::= <opt-whitespace> "<" <rule-name> ">" <opt-whitespace> "::=" <opt-whitespace> <expression> <line-end> +-- <opt-whitespace> ::= " " <opt-whitespace> | "" +-- <expression> ::= <list> | <list> <opt-whitespace> "|" <opt-whitespace> <expression> +-- <line-end> ::= <opt-whitespace> <EOL> | <line-end> <line-end> +-- <list> ::= <term> | <term> <opt-whitespace> <list> +-- <term> ::= <literal> | "<" <rule-name> ">" +-- <literal> ::= '"' <text1> '"' | "'" <text2> "'" +-- <text1> ::= "" | <character1> <text1> +-- <text2> ::= "" | <character2> <text2> +-- <character> ::= <letter> | <digit> | <symbol> +-- <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" +-- <digit> ::= "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" +-- <symbol> ::= "|" | " " | "-" | "!" | "#" | "$" | "%" | "&" | "(" | ")" | "*" | "+" | "," | "-" | "." | "/" | ":" | ";" | ">" | "=" | "<" | "?" | "@" | "[" | "\" | "]" | "^" | "_" | "`" | "{" | "}" | "~" +-- <character1> ::= <character> | "'" +-- <character2> ::= <character> | '"' +-- <rule-name> ::= <letter> | <rule-name> <rule-char> +-- <rule-char> ::= <letter> | <digit> | "-" + +local anything = patterns.anything +local separator = P("|") +local left = P("<") +local right = P(">") +local space = S(" \t\n\r\f") +local spaces = space^1 +local letter = R("AZ","az") +local digit = R("09") +local symbol = S([[| -!#$%&()*+,-./:;>=<?@[\]^_`{}~]]) +local text = (letter + digit + symbol^0) +local name = letter * (letter + digit + P("-"))^0 +local becomes = P("::=") +local extra = P("|") +local single = P("'") +local double = P('"') + +local t_spacing = token(whitespace,space^1) +local t_term = token("command",left) + * token("text",name) + * token("command",right) +local t_text = token("quote",single) + * token("text",text) + * token("quote",single) + + token("quote",double) + * token("text",text) + * token("quote",double) +local t_becomes = token("operator",becomes) +local t_extra = token("extra",extra) +local t_rest = token("default",anything) + +bnflexer._rules = { + { "whitespace", t_spacing }, + { "term", t_term }, + { "text", t_text }, + { "becomes", t_becomes }, + { "extra", t_extra }, + { "rest", t_rest }, +} + +bnflexer._tokenstyles = context.styleset + +bnflexer._foldpattern = left + right + +bnflexer._foldsymbols = { + _patterns = { + "<", + ">", + }, + ["grouping"] = { + ["<"] = 1, + [">"] = -1, + }, +} + +return bnflexer |