"unicodedata" --- Unicode データベース
**************************************

======================================================================

This module provides access to the Unicode Character Database (UCD)
which defines character properties for all Unicode characters. The
data contained in this database is compiled from the UCD version
16.0.0.

このモジュールは、ユニコード標準付録 #44 「 ユニコード文字データベース
」で定義されているのと同じ名前およびシンボルを使用します。このモジュー
ルは次のような関数を定義します:

参考:

  The Unicode HOWTO for more information about Unicode and how to use
  this module.

unicodedata.lookup(name)

   Look up character by name.  If a character with the given name is
   found, return the corresponding character.  If not found,
   "KeyError" is raised. For example:

      >>> unicodedata.lookup('LEFT CURLY BRACKET')
      '{'

   The characters returned by this function are the same as those
   produced by "\N" escape sequence in string literals. For example:

      >>> unicodedata.lookup('MIDDLE DOT') == '\N{MIDDLE DOT}'
      True

   バージョン 3.3 で変更: name aliases [1] と named sequences [2] のサ
   ポートが追加されました。

unicodedata.name(chr, default=None, /)

   Returns the name assigned to the character *chr* as a string. If no
   name is defined, *default* is returned, or, if not given,
   "ValueError" is raised. For example:

      >>> unicodedata.name('½')
      'VULGAR FRACTION ONE HALF'
      >>> unicodedata.name('\uFFFF', 'fallback')
      'fallback'

unicodedata.decimal(chr, default=None, /)

   Returns the decimal value assigned to the character *chr* as
   integer. If no such value is defined, *default* is returned, or, if
   not given, "ValueError" is raised. For example:

      >>> unicodedata.decimal('\N{ARABIC-INDIC DIGIT NINE}')
      9
      >>> unicodedata.decimal('\N{SUPERSCRIPT NINE}', -1)
      -1

unicodedata.digit(chr, default=None, /)

   Returns the digit value assigned to the character *chr* as integer.
   If no such value is defined, *default* is returned, or, if not
   given, "ValueError" is raised:

      >>> unicodedata.digit('\N{SUPERSCRIPT NINE}')
      9

unicodedata.numeric(chr, default=None, /)

   Returns the numeric value assigned to the character *chr* as float.
   If no such value is defined, *default* is returned, or, if not
   given, "ValueError" is raised:

      >>> unicodedata.numeric('½')
      0.5

unicodedata.category(chr)

   Returns the general category assigned to the character *chr* as
   string. General category names consist of two letters. See the
   General Category Values section of the Unicode Character Database
   documentation for a list of category codes. For example:

      >>> unicodedata.category('A')  # 'L'etter, 'u'ppercase
      'Lu'

unicodedata.bidirectional(chr)

   Returns the bidirectional class assigned to the character *chr* as
   string. If no such value is defined, an empty string is returned.
   See the Bidirectional Class Values section of the Unicode Character
   Database documentation for a list of bidirectional codes. For
   example:

      >>> unicodedata.bidirectional('\N{ARABIC-INDIC DIGIT SEVEN}') # 'A'rabic, 'N'umber
      'AN'

unicodedata.combining(chr)

   Returns the canonical combining class assigned to the character
   *chr* as integer. Returns "0" if no combining class is defined. See
   the Canonical Combining Class Values section of the Unicode
   Character Database for more information.

unicodedata.east_asian_width(chr)

   Returns the east asian width assigned to the character *chr* as
   string. For a list of widths and or more information, see the
   Unicode Standard Annex #11.

unicodedata.mirrored(chr)

   Returns the mirrored property assigned to the character *chr* as
   integer. Returns "1" if the character has been identified as a
   "mirrored" character in bidirectional text, "0" otherwise. For
   example:

      >>> unicodedata.mirrored('>')
      1

unicodedata.decomposition(chr)

   Returns the character decomposition mapping assigned to the
   character *chr* as string. An empty string is returned in case no
   such mapping is defined. For example:

      >>> unicodedata.decomposition('Ã')
      '0041 0303'

unicodedata.normalize(form, unistr)

   Unicode 文字列 *unistr* の正規形 *form* を返します。 *form* の有効
   な値は、'NFC'、'NFKC'、'NFD'、'NFKD' です。

   Unicode 規格は標準等価性 (canonical equivalence) と互換等価性
   (compatibility equivalence) に基づいて、様々な Unicode文字列の正規
   形を定義します。Unicode では、複数の方法で表現できる文字があります
   。たとえば、文字 U+00C7 (LATIN CAPITAL LETTER C WITH CEDILLA) は、
   U+0043 (LATIN CAPITAL LETTER C) U+0327 (COMBINING CEDILLA) というシ
   ーケンスとしても表現できます。

   各文字には2つの正規形があり、それぞれ正規形 C と正規形 D といいます
   。正規形 D (NFD) は標準分解 (canonical decomposition) としても知ら
   れており、各文字を分解された形に変換します。正規形 C (NFC) は標準分
   解を適用した後、結合済文字を再構成します。

   In addition to these two forms, there are two additional normal
   forms based on compatibility equivalence. In Unicode, certain
   characters are supported which normally would be unified with other
   characters. For example, U+2160 (ROMAN NUMERAL ONE) is really the
   same thing as U+0049 (LATIN CAPITAL LETTER I). However, it is
   supported in Unicode for compatibility with existing character sets
   (for example, gb2312).

   The normal form KD (NFKD) will apply the compatibility
   decomposition, that is, replace all compatibility characters with
   their equivalents. The normal form KC (NFKC) first applies the
   compatibility decomposition, followed by the canonical composition.

   2つのunicode文字列が正規化されていて人間の目に同じに見えても、片方
   が結合文字を持っていてもう片方が持っていない場合、それらは完全に同
   じではありません。

unicodedata.is_normalized(form, unistr)

   Unicode 文字列 *unistr* が正規形 *form* かどうかを返します。 *form*
   の有効な値は、'NFC'、'NFKC'、'NFD'、'NFKD' です。

   Added in version 3.8.

更に、本モジュールは以下の定数を公開します:

unicodedata.unidata_version

   このモジュールで使われている Unicode データベースのバージョン。

unicodedata.ucd_3_2_0

   これはモジュール全体と同じメソッドを具えたオブジェクトですが、
   Unicode データベースバージョン 3.2 を代わりに使っており、この特定の
   バージョンの Unicode データベースを必要とするアプリケーション(IDNA
   など)のためものです。

-[ 脚注 ]-

[1] https://www.unicode.org/Public/16.0.0/ucd/NameAliases.txt

[2] https://www.unicode.org/Public/16.0.0/ucd/NamedSequences.txt
