okkez です。

ちょっとバージョンごとに違うみたいです。

a.rb:
  s = 'abcd'
  p s[1..2]
  p s[2..2]
  p s[3..2]
  p s[4..2]
  p s[5..2]

  p s[1...2]
  p s[2...2]
  p s[3...2]
  p s[4...2]
  p s[5...2]


result.txt

ruby 1.8.0 (2003-08-04) [x86_64-linux]
"bc"
"c"
""
nil
nil
"b"
""
nil
nil
nil
ruby 1.8.1 (2003-12-25) [x86_64-linux]
"bc"
"c"
""
nil
nil
"b"
""
nil
nil
nil
ruby 1.8.2 (2004-12-25) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.8.3 (2005-09-21) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.8.4 (2005-12-24) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.8.5 (2008-06-20 patchlevel 231) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.8.6 (2009-09-09 patchlevel 388) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.8.7 (2010-07-17 patchlevel 300) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.8.7 (2010-12-23 patchlevel 330) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.8.8dev (2010-08-05 revision 26865) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.9.1p378 (2010-01-10 revision 26273) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.9.1p429 (2010-07-14 revision 28641) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.9.2p136 (2010-12-25 revision 30365) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.9.2p180 (2011-02-18 revision 30909) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil
ruby 1.9.3dev (2011-05-30 trunk 31825) [x86_64-linux]
"bc"
"c"
""
""
nil
"b"
""
""
""
nil


-- 
okkez
okkez000@g...

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