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, 108 deletions

diff --git a/lexers/makefile.lua b/lexers/makefile.lua
deleted file mode 100644
index 45eb310..0000000
--- a/lexers/makefile.lua
+++ /dev/null
@@ -1,108 +0,0 @@
--- Copyright 2006-2016 Mitchell mitchell.att.foicica.com. See LICENSE.
--- Makefile 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 = 'makefile'}
-
--- Whitespace.
-local ws = token(l.WHITESPACE, l.space^1)
-
--- Comments.
-local comment = token(l.COMMENT, '#' * l.nonnewline^0)
-
--- Keywords.
-local keyword = token(l.KEYWORD, P('!')^-1 * l.word_match({
-  -- GNU Make conditionals.
-  'ifeq', 'ifneq', 'ifdef', 'ifndef', 'else', 'endif',
-  -- Other conditionals.
-  'if', 'elseif', 'elseifdef', 'elseifndef',
-  -- Directives and other keywords.
-  'define', 'endef', 'export', 'include', 'override', 'private', 'undefine',
-  'unexport', 'vpath'
-}, nil, true))
-
--- Functions.
-local func = token(l.FUNCTION, l.word_match({
-  -- Functions for String Substitution and Analysis.
-  'subst', 'patsubst', 'strip', 'findstring', 'filter', 'filter-out', 'sort',
-  'word', 'wordlist', 'words', 'firstword', 'lastword',
-  -- Functions for File Names.
-  'dir', 'notdir', 'suffix', 'basename', 'addsuffix', 'addprefix', 'join',
-  'wildcard', 'realpath', 'abspath',
-  -- Functions for Conditionals.
-  'if', 'or', 'and',
-  -- Miscellaneous Functions.
-  'foreach', 'call', 'value', 'eval', 'origin', 'flavor', 'shell',
-  -- Functions That Control Make.
-  'error', 'warning', 'info'
-}), '-')
-
--- Variables.
-local word_char, assign = l.any - l.space - S(':#=(){}'), S(':+?')^-1 * '='
-local expanded_var = '$' * ('(' * word_char^1 * ')' + '{' * word_char^1 * '}')
-local auto_var = '$' * S('@%<?^+|*')
-local special_var = l.word_match({
-  'MAKEFILE_LIST', '.DEFAULT_GOAL', 'MAKE_RESTARTS', '.RECIPEPREFIX',
-  '.VARIABLES', '.FEATURES', '.INCLUDE_DIRS',
-  'GPATH', 'MAKECMDGOALS', 'MAKESHELL', 'SHELL', 'VPATH'
-}, '.') * #(ws^0 * assign)
-local implicit_var = l.word_match{
-  -- Some common variables.
-  'AR', 'AS', 'CC', 'CXX', 'CPP', 'FC', 'M2C', 'PC', 'CO', 'GET', 'LEX', 'YACC',
-  'LINT', 'MAKEINFO', 'TEX', 'TEXI2DVI', 'WEAVE', 'CWEAVE', 'TANGLE', 'CTANGLE',
-  'RM',
-  -- Some common flag variables.
-  'ARFLAGS', 'ASFLAGS', 'CFLAGS', 'CXXFLAGS', 'COFLAGS', 'CPPFLAGS', 'FFLAGS',
-  'GFLAGS', 'LDFLAGS', 'LFLAGS', 'YFLAGS', 'PFLAGS', 'RFLAGS', 'LINTFLAGS',
-  -- Other.
-  'DESTDIR', 'MAKE', 'MAKEFLAGS', 'MAKEOVERRIDES', 'MFLAGS'
-} * #(ws^0 * assign)
-local computed_var = token(l.OPERATOR, '$' * S('({')) * func
-local variable = token(l.VARIABLE,
-                       expanded_var + auto_var + special_var + implicit_var) +
-                 computed_var
-
--- Targets.
-local special_target = token(l.CONSTANT, l.word_match({
-  '.PHONY', '.SUFFIXES', '.DEFAULT', '.PRECIOUS', '.INTERMEDIATE', '.SECONDARY',
-  '.SECONDEXPANSION', '.DELETE_ON_ERROR', '.IGNORE', '.LOW_RESOLUTION_TIME',
-  '.SILENT', '.EXPORT_ALL_VARIABLES', '.NOTPARALLEL', '.ONESHELL', '.POSIX'
-}, '.'))
-local normal_target = token('target', (l.any - l.space - S(':#='))^1)
-local target = l.starts_line((special_target + normal_target) * ws^0 *
-                             #(':' * -P('=')))
-
--- Identifiers.
-local identifier = token(l.IDENTIFIER, word_char^1)
-
--- Operators.
-local operator = token(l.OPERATOR, assign + S(':$(){}'))
-
-M._rules = {
-  {'whitespace', ws},
-  {'keyword', keyword},
-  {'target', target},
-  {'variable', variable},
-  {'operator', operator},
-  {'identifier', identifier},
-  {'comment', comment},
-}
-
-M._tokenstyles = {
-  target = l.STYLE_LABEL
-}
-
-M._LEXBYLINE = true
-
--- Embedded Bash.
-local bash = l.load('bash')
-bash._RULES['variable'] = token(l.VARIABLE, '$$' * word_char^1) +
-                          bash._RULES['variable'] + variable
-local bash_start_rule = token(l.WHITESPACE, P('\t')) + token(l.OPERATOR, P(';'))
-local bash_end_rule = token(l.WHITESPACE, P('\n'))
-l.embed_lexer(M, bash, bash_start_rule, bash_end_rule)
-
-return M