Update Go library to r60.

From-SVN: r178910

libgo/go/bytes/bytes.go

@@ -212,24 +212,38 @@ func genSplit(s, sep []byte, sepSave, n int) [][]byte {
 	return a[0 : na+1]
 }
 
-// Split slices s into subslices separated by sep and returns a slice of
+// SplitN slices s into subslices separated by sep and returns a slice of
+// the subslices between those separators.
+// If sep is empty, SplitN splits after each UTF-8 sequence.
+// The count determines the number of subslices to return:
+//   n > 0: at most n subslices; the last subslice will be the unsplit remainder.
+//   n == 0: the result is nil (zero subslices)
+//   n < 0: all subslices
+func SplitN(s, sep []byte, n int) [][]byte { return genSplit(s, sep, 0, n) }
+
+// SplitAfterN slices s into subslices after each instance of sep and
+// returns a slice of those subslices.
+// If sep is empty, SplitAfterN splits after each UTF-8 sequence.
+// The count determines the number of subslices to return:
+//   n > 0: at most n subslices; the last subslice will be the unsplit remainder.
+//   n == 0: the result is nil (zero subslices)
+//   n < 0: all subslices
+func SplitAfterN(s, sep []byte, n int) [][]byte {
+	return genSplit(s, sep, len(sep), n)
+}
+
+// Split slices s into all subslices separated by sep and returns a slice of
 // the subslices between those separators.
 // If sep is empty, Split splits after each UTF-8 sequence.
-// The count determines the number of subslices to return:
-//   n > 0: at most n subslices; the last subslice will be the unsplit remainder.
-//   n == 0: the result is nil (zero subslices)
-//   n < 0: all subslices
-func Split(s, sep []byte, n int) [][]byte { return genSplit(s, sep, 0, n) }
+// It is equivalent to SplitN with a count of -1.
+func Split(s, sep []byte) [][]byte { return genSplit(s, sep, 0, -1) }
 
-// SplitAfter slices s into subslices after each instance of sep and
+// SplitAfter slices s into all subslices after each instance of sep and
 // returns a slice of those subslices.
-// If sep is empty, Split splits after each UTF-8 sequence.
-// The count determines the number of subslices to return:
-//   n > 0: at most n subslices; the last subslice will be the unsplit remainder.
-//   n == 0: the result is nil (zero subslices)
-//   n < 0: all subslices
-func SplitAfter(s, sep []byte, n int) [][]byte {
-	return genSplit(s, sep, len(sep), n)
+// If sep is empty, SplitAfter splits after each UTF-8 sequence.
+// It is equivalent to SplitAfterN with a count of -1.
+func SplitAfter(s, sep []byte) [][]byte {
+	return genSplit(s, sep, len(sep), -1)
 }
 
 // Fields splits the array s around each instance of one or more consecutive white space
@@ -384,7 +398,6 @@ func ToTitleSpecial(_case unicode.SpecialCase, s []byte) []byte {
 	return Map(func(r int) int { return _case.ToTitle(r) }, s)
 }
 
-
 // isSeparator reports whether the rune could mark a word boundary.
 // TODO: update when package unicode captures more of the properties.
 func isSeparator(rune int) bool {