# module Rouge
#   module Lexers
#     class D < RegexLexer
#       desc 'The D Programming language (http://dlang.org)'
#       tag 'd'
#       aliases 'dlang'
#       filenames '*.d'
# 
#       def self.keywords
#         @keywords ||= %w(
#           abstract alias align asm assert auto body bool break byte
#           case cast catch cdouble cent cfloat char class const continue
#           creal dchar debug default delegate delete deprecated do double
#           else enum export extern false final finally float for foreach
#           foreach_reverse function goto idouble if ifloat immutable
#           import in inout int interface invariant ireal is lazy long
#           macro mixin module new nothrow null out override package pragma
#           private protected public pure real ref return scope shared
#           short static struct super switch synchronized template this
#           throw true try typedef typeid typeof ubyte ucent uint ulong
#           union unittest ushort version void volatile wchar while with
#           __FILE__ __MODULE__ __LINE__ __FUNCTION__ __PRETTY_FUNCTION__
#           __gshared __traits __vector __parameters
#         )
#       end
# 
#       def self.builtins
#         @builtins ||= %w(
#           string wstring dstring size_t ptrdiff_t
#           __DATE__ __TIME__ __TIMESTAMP__ __VENDOR__ __VERSION__
#         )
#       end
# 
#       id = /[[:alpha:]_]\w*/
#       symmetric = {
#         '[' => ']',
#         '<' => '>',
#         '(' => ')',
#         '{' => '}'
#       }
# 
#       escapes = [
#         /\\['"?\\abfnrtv]/,
#         /\\[0-7]{1,3}/,
#         /\\x[0-9a-fA-F]{2}/,
#         /\\u[0-9a-fA-F]{4}/,
#         /\\U[0-9a-fA-F]{8}/,
#         /\\&\w+;/,
#       ]
# 
#       symmetric_open = Regexp.new "[#{Regexp.escape(symmetric.keys.join)}]"
# 
#       state :basic do
#         rule /\s+/m, 'Text'
#         rule %r(//.*$), 'Comment.Single'
#         rule %r(/[*].*?[*]/), 'Comment.Multiline'
#         rule %r(/[+]), 'Comment.Multiline', :nested_comment
#       end
# 
#       state :final_quote do
#         rule /"/, 'Literal.String', :pop!
#         rule /./, 'Error', :pop!
#       end
# 
#       state :nested_comment do
#         rule %r([+]/), :pop!
#         rule %r(/[+]), :nested_comment
#         rule %r([/+]|[^/+]+), 'Comment.Multiline'
#       end
# 
#       state :root do
#         rule /r".*?"/, 'Literal.String'
#         rule /`.*?`/, 'Literal.String'
#         rule /q"(#{id})\n.*?\n\1"/, 'Literal.String.Heredoc'
#         rule /q"(#{symmetric_open})/ do |m|
#           token 'Literal.String'
#           open = Regexp.escape(m[1])
#           close = Regexp.escape(symmetric[m[1]])
#           push :final_quote
#           push do
#             mixin :escapes
#             rule /\\[#{open}#{close}]/, 'Literal.String.Escape'
#             rule(/#{open}/) { token 'Literal.String'; push }
#             rule(/#{close}/) { token 'Literal.String'; pop! }
#             rule /[^\\#{open}#{close}]+/, 'Literal.String'
#           end
#         end
#         rule /q"(\S).*?\1"/, 'Literal.String'
#         # Token strings are going to be lexed like D, because
#         # they're frigging impossible otherwise.  I'll highlight
#         # the q as a string, though.
#         rule /q(?=[{])/, 'Literal.String'
#         rule /x"/, 'Literal.String.Other', :hex_string
#         rule /"/, 'Literal.String', :dq
#         rule /'/ do
#           token 'Literal.String.Char'
#           push :char_end; push :char
#         end
# 
#         # numbers
#         rule /0b[01_]+/, 'Literal.Number.Binary'
#         rule /0x[0-9a-f_]+/i, 
#         rule /\d+[ul]+/i, 'Literal.Number.Integer'
# 
#         rule /#{keywords.join('|')}/, 'Keyword'
#       end
# 
#       state :escapes do
#         escapes.each do |re|
#           rule re, 'Literal.String.Escape'
#         end
#       end
# 
#       state :char do
#         escapes.each do |re|
#           rule re, 'Literal.String.Char', :pop!
#         end
# 
#         rule /./, 'Literal.String.Char', :pop!
#       end
# 
#       state :hex_string do
#         rule /[0-9a-f]+/i, 'Literal.Number.Hex'
#         rule /\s+/m, 'Literal.String.Other'
#         rule /"/, 'Literal.String.Other', :pop!
#       end
# 
#       state :char_end do
#         rule /'[cwd]+/, 'Literal.String.Char', :pop!
#         rule /./, 'Error', :pop!
#       end
# 
#       state :dq do
#         mixin :escapes
#         rule /[^\\"]+/, 'Literal.String.Double'
#         rule /"/ do
#           token 'Literal.String.Double'
#           pop!; push :post_string
#         end
#       end
# 
#       state :post_string do
#         rule /[cwd]+/, 'Literal.String'
#         rule(//) { pop! }
#       end
#     end
#   end
# end