--- URI.escape(str[, unsafe])
--- URI.encode(str[, unsafe])

    URI ʸ򥨥󥳡ɤʸ֤ޤunsafe ˤϡURI 
    ȤƻǤʤʸɽʸǻꤷޤ(ǥեȤϡ
     URI::UNSAFE
        /[^-_.!~*'()a-zA-Z\d;\/?:@&=+$,\[\]]/n
    Ǥ)

        require 'uri'
        $KCODE = 'EUC'
        p URI.escape('http://www.ruby-lang.org/ja/man-1.6/?cmd=view;name=Rubyե󥹥ޥ˥奢')

        => "http://www.ruby-lang.org/ja/man-1.6/?cmd=view;name=Ruby%A5%EA%A5%D5%A5%A1%A5%EC%A5%F3%A5%B9%A5%DE%A5%CB%A5%E5%A5%A2%A5%EB"

