Encoding-free String comparison
Currently, strings with the same content but with different encodings count as different strings. This causes strange behaviour as below (noted in StackOverflow question http://stackoverflow.com/questions/19977788/strange-behavior-in-packed-ruby-strings#19978206):
.pack("C") # => "\x80" .pack("C") == "\x80" # => false
.pack("C") has the encoding ASCII-8BIT and
"\x80" (by default) has the encoding UTF-8, the two strings are not equal.
Also, comparison of strings with different encodings may end up with a messy, unintended result.
I suggest that the comparison
String#<=> should not be based on the respective encoding of the strings, but all the strings should be internally converted to UTF-8 for the purpose of comparison.