lexers/erlang.lua

   1 -- Copyright 2006-2016 Mitchell mitchell.att.foicica.com. See LICENSE.
   2 -- Erlang LPeg lexer.
   3
   4 local l = require('lexer')
   5 local token, word_match = l.token, l.word_match
   6 local P, R, S = lpeg.P, lpeg.R, lpeg.S
   7
   8 local M = {_NAME = 'erlang'}
   9
  10 -- Whitespace.
  11 local ws = token(l.WHITESPACE, l.space^1)
  12
  13 -- Comments.
  14 local comment = token(l.COMMENT, '%' * l.nonnewline^0)
  15
  16 -- Strings.
  17 local sq_str = l.delimited_range("'", true)
  18 local dq_str = l.delimited_range('"')
  19 local literal = '$' * l.any * l.alnum^0
  20 local string = token(l.STRING, sq_str + dq_str + literal)
  21
  22 -- Numbers.
  23 local number = token(l.NUMBER, l.float + l.integer)
  24
  25 -- Keywords.
  26 local keyword = token(l.KEYWORD, word_match{
  27   'after', 'begin', 'case', 'catch', 'cond', 'end', 'fun', 'if', 'let', 'of',
  28   'query', 'receive', 'when',
  29   -- Operators.
  30   'div', 'rem', 'or', 'xor', 'bor', 'bxor', 'bsl', 'bsr', 'and', 'band', 'not',
  31   'bnot',
  32   'badarg', 'nocookie', 'false', 'true'
  33 })
  34
  35 -- Functions.
  36 local func = token(l.FUNCTION, word_match{
  37   'abs', 'alive', 'apply', 'atom_to_list', 'binary_to_list', 'binary_to_term',
  38   'concat_binary', 'date', 'disconnect_node', 'element', 'erase', 'exit',
  39   'float', 'float_to_list', 'get', 'get_keys', 'group_leader', 'halt', 'hd',
  40   'integer_to_list', 'is_alive', 'length', 'link', 'list_to_atom',
  41   'list_to_binary', 'list_to_float', 'list_to_integer', 'list_to_pid',
  42   'list_to_tuple', 'load_module', 'make_ref', 'monitor_node', 'node', 'nodes',
  43   'now', 'open_port', 'pid_to_list', 'process_flag', 'process_info', 'process',
  44   'put', 'register', 'registered', 'round', 'self', 'setelement', 'size',
  45   'spawn', 'spawn_link', 'split_binary', 'statistics', 'term_to_binary',
  46   'throw', 'time', 'tl', 'trunc', 'tuple_to_list', 'unlink', 'unregister',
  47   'whereis',
  48   -- Others.
  49   'atom', 'binary', 'constant', 'function', 'integer', 'list', 'number', 'pid',
  50   'ports', 'port_close', 'port_info', 'reference', 'record',
  51   -- Erlang:.
  52   'check_process_code', 'delete_module', 'get_cookie', 'hash', 'math',
  53   'module_loaded', 'preloaded', 'processes', 'purge_module', 'set_cookie',
  54   'set_node',
  55   -- Math.
  56   'acos', 'asin', 'atan', 'atan2', 'cos', 'cosh', 'exp', 'log', 'log10', 'pi',
  57   'pow', 'power', 'sin', 'sinh', 'sqrt', 'tan', 'tanh'
  58 })
  59
  60 -- Identifiers.
  61 local identifier = token(l.IDENTIFIER, l.word)
  62
  63 -- Operators.
  64 local operator = token(l.OPERATOR, S('-<>.;=/|#+*:,?!()[]{}'))
  65
  66 -- Directives.
  67 local directive = token('directive', '-' * word_match{
  68   'author', 'compile', 'copyright', 'define', 'doc', 'else', 'endif', 'export',
  69   'file', 'ifdef', 'ifndef', 'import', 'include_lib', 'include', 'module',
  70   'record', 'undef'
  71 })
  72
  73 M._rules = {
  74   {'whitespace', ws},
  75   {'keyword', keyword},
  76   {'function', func},
  77   {'identifier', identifier},
  78   {'directive', directive},
  79   {'string', string},
  80   {'comment', comment},
  81   {'number', number},
  82   {'operator', operator},
  83 }
  84
  85 M._tokenstyles = {
  86   directive = l.STYLE_PREPROCESSOR
  87 }
  88
  89 M._foldsymbols = {
  90   _patterns = {'[a-z]+', '[%(%)%[%]{}]', '%%'},
  91   [l.KEYWORD] = {
  92     case = 1, fun = 1, ['if'] = 1, query = 1, receive = 1, ['end'] = -1
  93   },
  94   [l.OPERATOR] = {
  95     ['('] = 1, [')'] = -1, ['['] = 1, [']'] = -1, ['{'] = 1, ['}'] = -1
  96   },
  97   [l.COMMENT] = {['%'] = l.fold_line_comments('%')}
  98 }
  99
 100 return M