Move all lua related files to lua/ subfolder

Also remove the lexers sub directory from the Lua search path.
As a result we attempt to open fewer files during startup:

 $ strace -e open -o log ./vis +q config.h && wc -l log

In order to avoid having to modifiy all lexers which `require('lexer')`
we instead place a symlink in the top level directory.

 $ ./configure --disable-lua
 $ rm -rf lua

Should result in a source tree with most lua specifc functionality
removed.

1 files changed, 0 insertions, 100 deletions

diff --git a/lexers/erlang.lua b/lexers/erlang.lua
deleted file mode 100644
index a741d63..0000000
--- a/lexers/erlang.lua
+++ /dev/null
@@ -1,100 +0,0 @@
--- Copyright 2006-2016 Mitchell mitchell.att.foicica.com. See LICENSE.
--- Erlang LPeg lexer.
-
-local l = require('lexer')
-local token, word_match = l.token, l.word_match
-local P, R, S = lpeg.P, lpeg.R, lpeg.S
-
-local M = {_NAME = 'erlang'}
-
--- Whitespace.
-local ws = token(l.WHITESPACE, l.space^1)
-
--- Comments.
-local comment = token(l.COMMENT, '%' * l.nonnewline^0)
-
--- Strings.
-local sq_str = l.delimited_range("'", true)
-local dq_str = l.delimited_range('"')
-local literal = '$' * l.any * l.alnum^0
-local string = token(l.STRING, sq_str + dq_str + literal)
-
--- Numbers.
-local number = token(l.NUMBER, l.float + l.integer)
-
--- Keywords.
-local keyword = token(l.KEYWORD, word_match{
-  'after', 'begin', 'case', 'catch', 'cond', 'end', 'fun', 'if', 'let', 'of',
-  'query', 'receive', 'when',
-  -- Operators.
-  'div', 'rem', 'or', 'xor', 'bor', 'bxor', 'bsl', 'bsr', 'and', 'band', 'not',
-  'bnot',
-  'badarg', 'nocookie', 'false', 'true'
-})
-
--- Functions.
-local func = token(l.FUNCTION, word_match{
-  'abs', 'alive', 'apply', 'atom_to_list', 'binary_to_list', 'binary_to_term',
-  'concat_binary', 'date', 'disconnect_node', 'element', 'erase', 'exit',
-  'float', 'float_to_list', 'get', 'get_keys', 'group_leader', 'halt', 'hd',
-  'integer_to_list', 'is_alive', 'length', 'link', 'list_to_atom',
-  'list_to_binary', 'list_to_float', 'list_to_integer', 'list_to_pid',
-  'list_to_tuple', 'load_module', 'make_ref', 'monitor_node', 'node', 'nodes',
-  'now', 'open_port', 'pid_to_list', 'process_flag', 'process_info', 'process',
-  'put', 'register', 'registered', 'round', 'self', 'setelement', 'size',
-  'spawn', 'spawn_link', 'split_binary', 'statistics', 'term_to_binary',
-  'throw', 'time', 'tl', 'trunc', 'tuple_to_list', 'unlink', 'unregister',
-  'whereis',
-  -- Others.
-  'atom', 'binary', 'constant', 'function', 'integer', 'list', 'number', 'pid',
-  'ports', 'port_close', 'port_info', 'reference', 'record',
-  -- Erlang:.
-  'check_process_code', 'delete_module', 'get_cookie', 'hash', 'math',
-  'module_loaded', 'preloaded', 'processes', 'purge_module', 'set_cookie',
-  'set_node',
-  -- Math.
-  'acos', 'asin', 'atan', 'atan2', 'cos', 'cosh', 'exp', 'log', 'log10', 'pi',
-  'pow', 'power', 'sin', 'sinh', 'sqrt', 'tan', 'tanh'
-})
-
--- Identifiers.
-local identifier = token(l.IDENTIFIER, l.word)
-
--- Operators.
-local operator = token(l.OPERATOR, S('-<>.;=/|#+*:,?!()[]{}'))
-
--- Directives.
-local directive = token('directive', '-' * word_match{
-  'author', 'compile', 'copyright', 'define', 'doc', 'else', 'endif', 'export',
-  'file', 'ifdef', 'ifndef', 'import', 'include_lib', 'include', 'module',
-  'record', 'undef'
-})
-
-M._rules = {
-  {'whitespace', ws},
-  {'keyword', keyword},
-  {'function', func},
-  {'identifier', identifier},
-  {'directive', directive},
-  {'string', string},
-  {'comment', comment},
-  {'number', number},
-  {'operator', operator},
-}
-
-M._tokenstyles = {
-  directive = l.STYLE_PREPROCESSOR
-}
-
-M._foldsymbols = {
-  _patterns = {'[a-z]+', '[%(%)%[%]{}]', '%%'},
-  [l.KEYWORD] = {
-    case = 1, fun = 1, ['if'] = 1, query = 1, receive = 1, ['end'] = -1
-  },
-  [l.OPERATOR] = {
-    ['('] = 1, [')'] = -1, ['['] = 1, [']'] = -1, ['{'] = 1, ['}'] = -1
-  },
-  [l.COMMENT] = {['%'] = l.fold_line_comments('%')}
-}
-
-return M