Added optional Lua lexer support.

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

1 files changed, 60 insertions, 0 deletions

diff --git a/lexlua/eiffel.lua b/lexlua/eiffel.lua
new file mode 100644
index 000000000..64ccd8bf3
--- /dev/null
+++ b/lexlua/eiffel.lua
@@ -0,0 +1,60 @@
+-- Copyright 2006-2018 Mitchell mitchell.att.foicica.com. See License.txt.
+-- Eiffel 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('eiffel')
+
+-- Whitespace.
+lex:add_rule('whitespace', token(lexer.WHITESPACE, lexer.space^1))
+
+-- Keywords.
+lex:add_rule('keyword', token(lexer.KEYWORD, word_match[[
+  alias all and as check class creation debug deferred do else elseif end ensure
+  expanded export external feature from frozen if implies indexing infix inherit
+  inspect invariant is like local loop not obsolete old once or prefix redefine
+  rename require rescue retry select separate then undefine until variant when
+  xor
+  current false precursor result strip true unique void
+]]))
+
+-- Types.
+lex:add_rule('type', token(lexer.TYPE, word_match[[
+  character string bit boolean integer real none any
+]]))
+
+-- Identifiers.
+lex:add_rule('identifier', token(lexer.IDENTIFIER, lexer.word))
+
+-- Strings.
+lex:add_rule('string', token(lexer.STRING, lexer.delimited_range("'", true) +
+                                           lexer.delimited_range('"', true)))
+
+-- Comments.
+lex:add_rule('comment', token(lexer.COMMENT, '--' * lexer.nonnewline^0))
+
+-- Numbers.
+lex:add_rule('number', token(lexer.NUMBER, lexer.float + lexer.integer))
+
+-- Operators.
+lex:add_rule('operator', token(lexer.OPERATOR, S('=!<>+-/*%&|^~.,:;?()[]{}')))
+
+-- Fold points.
+lex:add_fold_point(lexer.KEYWORD, 'check', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'debug', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'deferred', function(text, pos, line, s)
+  return line:find('deferred%s+class') and 0 or 1
+end)
+lex:add_fold_point(lexer.KEYWORD, 'do', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'from', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'if', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'inspect', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'once', 'end')
+lex:add_fold_point(lexer.KEYWORD, 'class', function(text, pos, line, s)
+  return line:find('deferred%s+class') and 0 or 1
+end)
+lex:add_fold_point(lexer.COMMENT, '--', lexer.fold_line_comments('--'))
+
+return lex