lexlua: Added Fennel lexer.

Thanks to Momohime Honda.

1 files changed, 37 insertions, 0 deletions

diff --git a/lexlua/fennel.lua b/lexlua/fennel.lua
new file mode 100644
index 000000000..19db55bea
--- /dev/null
+++ b/lexlua/fennel.lua
@@ -0,0 +1,37 @@
+-- Copyright 2006-2020 Mitchell mitchell.att.foicica.com. See License.txt.
+-- Fennel LPeg lexer.
+-- Contributed by Momohime Honda.
+
+local lexer = require('lexer')
+local token, word_match = lexer.token, lexer.word_match
+local P, S = lpeg.P, lpeg.S
+
+local lex = lexer.new('fennel', {inherit = lexer.load('lua')})
+
+-- Whitespace.
+lex:add_rule('whitespace', token(lexer.WHITESPACE, lexer.space^1))
+
+-- Keywords.
+lex:modify_rule('keyword', token(lexer.KEYWORD, word_match[[
+  % * + - ->> -> -?>> -?> .. . // / : <= < = >= > ^ ~= λ
+  and comment do doc doto each eval-compiler fn for global hashfn if include
+  lambda length let local lua macro macros match not not= or partial quote
+  require-macros set set-forcibly! tset values var when while
+]]))
+
+-- Identifiers.
+local initial = lexer.alpha + S"|$%&#*+-./:<=>?~^_λ!"
+local subsequent = initial + lexer.digit
+lex:modify_rule('identifier', token(lexer.IDENTIFIER, initial * subsequent^0))
+
+-- Strings.
+lex:modify_rule('string', token(lexer.STRING, lexer.range('"')))
+
+-- Comments.
+lex:modify_rule('comment', token(lexer.COMMENT, lexer.to_eol(';')))
+
+-- Ignore these rules.
+lex:modify_rule('label', P(false))
+lex:modify_rule('operator', P(false))
+
+return lex