http://unicode.org/charts/PDF/UFF00.pdf

To detect:

[\x{FF01}-\x{FF60}\x{FFE0}-\x{FFE6}]Full widths ASCII variants, brackets and symbols
[\x{FF01}-\x{FF5E}]Full widths ASCII variants
[\x{FF21}-\x{FF3A}]Full widths ASCII uppercase letters
[\x{FF41}-\x{FF5A}]Full widths ASCII lowercase letters
[\x{FF10}-\x{FF19}]Full widths ASCII digits

To convert:

my %fullwidth_to_narrow = map chr, (
   ( map { $_ => $_-0xFF01+0x21 } 0xFF01..0xFF5E ),
   0xFF5F => 0x2985,
   0xFF60 => 0x2986,
   0xFFE0 => 0x00A2,
   0xFFE1 => 0x00A3,
   0xFFE2 => 0x00AC,
   0xFFE3 => 0x00AF,
   0xFFE4 => 0x00A6,
   0xFFE5 => 0x00A5,
   0xFFE6 => 0x20A9,
);

[download]

In reply to Re^3: Japanese: detect hiragana/katakana/fulll width eisuuji by ikegami
in thread Japanese: detect hiragana/katakana/fulll width eisuuji by GaijinPunch

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