vis

a vi-like editor based on Plan 9's structural regular expressions
template.txt

(958B)
      1 -- Copyright 2022-2025 Mitchell. See LICENSE.
      2 -- ? LPeg lexer.
      3 
      4 local lexer = lexer
      5 local P, S = lpeg.P, lpeg.S
      6 
      7 local lex = lexer.new(...)
      8 
      9 -- Keywords.
     10 lex:add_rule('keyword', lex:tag(lexer.KEYWORD, lex:word_match(lexer.KEYWORD)))
     11 
     12 -- Identifiers.
     13 lex:add_rule('identifier', lex:tag(lexer.IDENTIFIER, lexer.word))
     14 
     15 -- Strings.
     16 local sq_str = lexer.range("'")
     17 local dq_str = lexer.range('"')
     18 lex:add_rule('string', lex:tag(lexer.STRING, sq_str + dq_str))
     19 
     20 -- Comments.
     21 lex:add_rule('comment', lex:tag(lexer.COMMENT, lexer.to_eol('#')))
     22 
     23 -- Numbers.
     24 lex:add_rule('number', lex:tag(lexer.NUMBER, lexer.number))
     25 
     26 -- Operators.
     27 lex:add_rule('operator', lex:tag(lexer.OPERATOR, S('+-*/%^=<>,.{}[]()')))
     28 
     29 -- Fold points.
     30 lex:add_fold_point(lexer.KEYWORD, 'start', 'end')
     31 lex:add_fold_point(lexer.OPERATOR, '{', '}')
     32 
     33 -- Word lists.
     34 lex:set_word_list(lexer.KEYWORD, {
     35   'keyword1', 'keyword2', 'keyword3'
     36 })
     37 
     38 lexer.property['scintillua.comment'] = '#'
     39 
     40 return lex