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h1. #Multilingualization (m17n) inconsistencies between Ruby1.8 and Ruby1.9
* String class
** Ruby 1.8: Array of bytes
+ include Enumerable => String can be used like an Array)
+ 'String#[0]' returns ascii code
** Ruby 1.9: encoded characters (not Array but [] method is available)
+ String class behavior changes depending on the encoding
+ 'String#[0]' does not return ascii code (ex. use String#unpack('C*')[0], String.bytes.to_a[0])
+ not include Enumerable module (ex. String#each does not work)
+ we cannot use binary data (byte data) directly through String class
+ we have to set 'ascii-8bit' as an encoding for binary data
Magic comment
* we have to write encoding (magic comment) in each script
* 'File.read' cannot read binary file anymore (Ruby 1.8 can)
* ex. instead of 's = File.read("input.dat")'
s = open("input.dat","rb"){|f| f.read}
* Careful points from 1.8 to 1.9 (encoding)
o String#[0] does not return ascii code (this does not output an error, the behavior changes)
o Put magic comment (encoding) if there are non-ascii characters in source code (in most of the cases, an error comes)
o Pay attention to the encoding when we use String class, binary data, regular expression
o We cannot use Enumerable methods for a String instance
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