Added optional Lua lexer support.

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

1 files changed, 61 insertions, 0 deletions

diff --git a/lexlua/icon.lua b/lexlua/icon.lua
new file mode 100644
index 000000000..2759b3946
--- /dev/null
+++ b/lexlua/icon.lua
@@ -0,0 +1,61 @@
+-- Copyright 2006-2018 Mitchell mitchell.att.foicica.com. See License.txt.
+-- LPeg lexer for the Icon programming language.
+-- http://www.cs.arizona.edu/icon
+-- Contributed by Carl Sturtivant.
+
+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('icon')
+
+-- Whitespace.
+lex:add_rule('whitespace', token(lexer.WHITESPACE, lexer.space^1))
+
+-- Keywords.
+lex:add_rule('keyword', token(lexer.KEYWORD, word_match[[
+  break by case create default do else end every fail global if initial
+  invocable link local next not of procedure record repeat return static suspend
+  then to until while
+]]))
+
+-- Icon Keywords: unique to Icon.
+lex:add_rule('special_keyword', token('special_keyword', P('&') * word_match[[
+  allocated ascii clock collections cset current date dateline digits dump e
+  error errornumber errortext errorvalue errout fail features file host input
+  lcase letters level line main null output phi pi pos progname random regions
+  source storage subject time trace ucase version
+]]))
+lex:add_style('special_keyword', lexer.STYLE_TYPE)
+
+-- Identifiers.
+lex:add_rule('identifier', token(lexer.IDENTIFIER, lexer.word))
+
+-- Strings.
+lex:add_rule('string', token(lexer.STRING, lexer.delimited_range("'") +
+                                           lexer.delimited_range('"')))
+
+-- Comments.
+lex:add_rule('comment', token(lexer.COMMENT, '#' * lexer.nonnewline_esc^0))
+
+-- Numbers.
+local radix_literal = P('-')^-1 * lexer.dec_num * S('rR') * lexer.alnum^1
+lex:add_rule('number', token(lexer.NUMBER, radix_literal + lexer.float +
+                                           lexer.integer))
+
+-- Preprocessor.
+local preproc_word = word_match[[
+  define else endif error ifdef ifndef include line undef
+]]
+lex:add_rule('preproc', token(lexer.PREPROCESSOR, P('$') * preproc_word))
+
+-- Operators.
+lex:add_rule('operator', token(lexer.OPERATOR, S('+-/*%<>~!=^&|?~@:;,.()[]{}')))
+
+-- Fold points.
+lex:add_fold_point(lexer.PREPROCESSOR, 'ifdef', 'endif')
+lex:add_fold_point(lexer.PREPROCESSOR, 'ifndef', 'endif')
+lex:add_fold_point(lexer.KEYWORD, 'procedure', 'end')
+lex:add_fold_point(lexer.COMMENT, '#', lexer.fold_line_comments('#'))
+
+return lex