Added optional Lua lexer support.

This support is disabled by default and must be enabled via compile-time option.

1 files changed, 45 insertions, 0 deletions

diff --git a/lexlua/bibtex.lua b/lexlua/bibtex.lua
new file mode 100644
index 000000000..bdca1a807
--- /dev/null
+++ b/lexlua/bibtex.lua
@@ -0,0 +1,45 @@
+-- Copyright 2006-2018 Mitchell mitchell.att.foicica.com. See License.txt.
+-- Bibtex LPeg lexer.
+
+local lexer = require('lexer')
+local token, word_match = lexer.token, lexer.word_match
+local P, R, S = lpeg.P, lpeg.R, lpeg.S
+
+local lex = lexer.new('bibtex')
+
+-- Whitespace.
+local ws = token(lexer.WHITESPACE, lexer.space^1)
+
+-- Fields.
+lex:add_rule('field', token('field', word_match[[
+  author title journal year volume number pages month note key publisher editor
+  series address edition howpublished booktitle organization chapter school
+  institution type isbn issn affiliation issue keyword url
+]]))
+lex:add_style('field', lexer.STYLE_CONSTANT)
+
+-- Identifiers.
+lex:add_rule('identifier', token(lexer.IDENTIFIER, lexer.word))
+
+-- Strings.
+lex:add_rule('string', token(lexer.STRING,
+                             lexer.delimited_range('"') +
+                             lexer.delimited_range('{}', false, true, true)))
+
+-- Operators.
+lex:add_rule('operator', token(lexer.OPERATOR, S(',=')))
+
+-- Embedded in Latex.
+local latex = lexer.load('latex')
+
+-- Embedded Bibtex.
+local entry = token('entry', P('@') * word_match([[
+  book article booklet conference inbook incollection inproceedings manual
+  mastersthesis lambda misc phdthesis proceedings techreport unpublished
+]], true))
+lex:add_style('entry', lexer.STYLE_PREPROCESSOR)
+local bibtex_start_rule = entry * ws^0 * token(lexer.OPERATOR, P('{'))
+local bibtex_end_rule = token(lexer.OPERATOR, P('}'))
+latex:embed(lex, bibtex_start_rule, bibtex_end_rule)
+
+return lex