Unicode から cp932 に変換できない文字を知る 注意: gist には CP932 の文字コードではファイルを置けなかったので ここにある convert-cp932-valid-to-cp932.txt の文字コードは誤っている(UTF-8になっている)

convert-cp932-invalid-to-utf8.txt

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convert-cp932-valid-to-cp932.txt

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convert-cp932-valid-to-utf8.txt

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generate-cp932-invalid-chars.rb

cp932valid =
  [
   "\uFF5E", # FULL WIDTH TILDE
   "\u2225", # PARALLEL TO
   "\uFF0D", # FULLWIDTH HYPHEN-MINUS
   "\uFFE0", # FULLWIDTH CENT SIGN
   "\uFFE1", # FULLWIDTH POUND SIGN
   "\uFFE2"  # FULLWIDTH NOT SIGN
  ]

cp932invalid =
  [
   "\u301C", # WAVE DASH
   "\u2016", # DOUBLE VERTICAL LINE
   "\u2212", # MINUS SIGN
   "\u00A2", # CENT SIGN
   "\u00A3", # POUND SIGN
   "\u00AC"  # NOT SIGN
  ]

File.write('convert-cp932-valid-to-cp932.txt'  , cp932valid.map   {|s| s.encode("CP932") }.join("\n"))
File.write('convert-cp932-valid-to-utf8.txt'   , cp932valid.map   {|s| s.encode("UTF-8") }.join("\n"))
#File.write('convert-cp932-invalid-to-cp932.txt', cp932invalid.map {|s| s.encode("CP932") }.join("\n")) # raise error
File.write('convert-cp932-invalid-to-utf8.txt' , cp932invalid.map {|s| s.encode("UTF-8") }.join("\n"))