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, 97 deletions

diff --git a/lexers/rexx.lua b/lexers/rexx.lua
deleted file mode 100644
index c750168..0000000
--- a/lexers/rexx.lua
+++ /dev/null
@@ -1,97 +0,0 @@
--- Copyright 2006-2016 Mitchell mitchell.att.foicica.com. See LICENSE.
--- Rexx 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 = 'rexx'}
-
--- Whitespace.
-local ws = token(l.WHITESPACE, l.space^1)
-
--- Comments.
-local line_comment = '--' * l.nonnewline_esc^0
-local block_comment = l.nested_pair('/*', '*/')
-local comment = token(l.COMMENT, line_comment + block_comment)
-
--- Strings.
-local sq_str = l.delimited_range("'", true, true)
-local dq_str = l.delimited_range('"', true, true)
-local string = token(l.STRING, sq_str + dq_str)
-
--- Numbers.
-local number = token(l.NUMBER, l.float + l.integer)
-
--- Preprocessor.
-local preproc = token(l.PREPROCESSOR, l.starts_line('#') * l.nonnewline^0)
-
--- Keywords.
-local keyword = token(l.KEYWORD, word_match({
-  'address', 'arg', 'by', 'call', 'class', 'do', 'drop', 'else', 'end', 'exit',
-  'expose', 'forever', 'forward', 'guard', 'if', 'interpret', 'iterate',
-  'leave', 'method', 'nop', 'numeric', 'otherwise', 'parse', 'procedure',
-  'pull', 'push', 'queue', 'raise', 'reply', 'requires', 'return', 'routine',
-  'result', 'rc', 'say', 'select', 'self', 'sigl', 'signal', 'super', 'then',
-  'to', 'trace', 'use', 'when', 'while', 'until'
-}, nil, true))
-
--- Functions.
-local func = token(l.FUNCTION, word_match({
-  'abbrev', 'abs', 'address', 'arg', 'beep', 'bitand', 'bitor', 'bitxor', 'b2x',
-  'center', 'changestr', 'charin', 'charout', 'chars', 'compare', 'consition',
-  'copies', 'countstr', 'c2d', 'c2x', 'datatype', 'date', 'delstr', 'delword',
-  'digits', 'directory', 'd2c', 'd2x', 'errortext', 'filespec', 'form',
-  'format', 'fuzz', 'insert', 'lastpos', 'left', 'length', 'linein', 'lineout',
-  'lines', 'max', 'min', 'overlay', 'pos', 'queued', 'random', 'reverse',
-  'right', 'sign', 'sourceline', 'space', 'stream', 'strip', 'substr',
-  'subword', 'symbol', 'time', 'trace', 'translate', 'trunc', 'value', 'var',
-  'verify', 'word', 'wordindex', 'wordlength', 'wordpos', 'words', 'xrange',
-  'x2b', 'x2c', 'x2d', 'rxfuncadd', 'rxfuncdrop', 'rxfuncquery', 'rxmessagebox',
-  'rxwinexec', 'sysaddrexxmacro', 'sysbootdrive', 'sysclearrexxmacrospace',
-  'syscloseeventsem', 'sysclosemutexsem', 'syscls', 'syscreateeventsem',
-  'syscreatemutexsem', 'syscurpos', 'syscurstate', 'sysdriveinfo',
-  'sysdrivemap', 'sysdropfuncs', 'sysdroprexxmacro', 'sysdumpvariables',
-  'sysfiledelete', 'sysfilesearch', 'sysfilesystemtype', 'sysfiletree',
-  'sysfromunicode', 'systounicode', 'sysgeterrortext', 'sysgetfiledatetime',
-  'sysgetkey', 'sysini', 'sysloadfuncs', 'sysloadrexxmacrospace', 'sysmkdir',
-  'sysopeneventsem', 'sysopenmutexsem', 'sysposteventsem', 'syspulseeventsem',
-  'sysqueryprocess', 'sysqueryrexxmacro', 'sysreleasemutexsem',
-  'sysreorderrexxmacro', 'sysrequestmutexsem', 'sysreseteventsem', 'sysrmdir',
-  'syssaverexxmacrospace', 'syssearchpath', 'syssetfiledatetime',
-  'syssetpriority', 'syssleep', 'sysstemcopy', 'sysstemdelete', 'syssteminsert',
-  'sysstemsort', 'sysswitchsession', 'syssystemdirectory', 'systempfilename',
-  'systextscreenread', 'systextscreensize', 'sysutilversion', 'sysversion',
-  'sysvolumelabel', 'syswaiteventsem', 'syswaitnamedpipe', 'syswindecryptfile',
-  'syswinencryptfile', 'syswinver'
-}, '2', true))
-
--- Identifiers.
-local word = l.alpha * (l.alnum + S('@#$\\.!?_'))^0
-local identifier = token(l.IDENTIFIER, word)
-
--- Operators.
-local operator = token(l.OPERATOR, S('=!<>+-/\\*%&|^~.,:;(){}'))
-
-M._rules = {
-  {'whitespace', ws},
-  {'keyword', keyword},
-  {'function', func},
-  {'identifier', identifier},
-  {'string', string},
-  {'comment', comment},
-  {'number', number},
-  {'preproc', preproc},
-  {'operator', operator},
-}
-
-M._foldsymbols = {
-  _patterns = {'[a-z]+', '/%*', '%*/', '%-%-', ':'},
-  [l.KEYWORD] = {['do'] = 1, select = 1, ['end'] = -1, ['return'] = -1},
-  [l.COMMENT] = {
-    ['/*'] = 1, ['*/'] = -1, ['--'] = l.fold_line_comments('--')
-  },
-  [l.OPERATOR] = {[':'] = 1}
-}
-
-return M