以下のように空白を含むフォントを指定すると
RuntimeErrorになるのは仕様と言ってよいでしょうか。

  irb(main):001:0> require 'tk'
  => true
  irb(main):002:0> TkFont.families.grep(/arial/)
  => ["greek arial"]
  irb(main):003:0> TkFont.new('greek arial')
  RuntimeError: expected integer but got "arial"
	  from /usr/lib/ruby/1.8/tk.rb:1623:in `__invoke'
	  from /usr/lib/ruby/1.8/tk.rb:1623:in `_invoke'
	  from /usr/lib/ruby/1.8/tk.rb:1027:in `tk_call'
	  from /usr/lib/ruby/1.8/tkfont.rb:663:in `actual_core'
	  from /usr/lib/ruby/1.8/tkfont.rb:483:in `create_latinfont'
	  from /usr/lib/ruby/1.8/tkfont.rb:544:in `create_compoundfont'
	  from /usr/lib/ruby/1.8/tkfont.rb:318:in `initialize'
	  from (irb):3:in `new'
	  from (irb):3
  irb(main):004:0> TkFont.new('greek\ arial')
  => #<TkFont:0x41245b60 @latinfont="@font00002l", @fontslot={"font"=>"@font00002c"}, @kanji_desscendant=nil, @compoundfont="@font00002c", @id="@font00002", @kanjifont="@font00002k", @latin_desscendant=nil>

-- 
やまだあきら / akira yamada <URL:http://arika.org>
Vine Caves, Ltd. <URL:http://vinecaves.com>
(akira / arika.org, akira / debian.org or akira / vinecaves.com)