@spec block_index(non_neg_integer()) :: non_neg_integer()

Get the CJK block index for a codepoint.

Maps a codepoint to its CJK Unified Ideograph block for use in the radical-stroke sort key.

Arguments

• cp - an integer codepoint.

Returns

An integer block index:

• 0 - CJK Unified Ideographs (U+4E00..U+9FFF).
• 1 - Extension A (U+3400..U+4DBF).
• 2 - Extension B (U+20000..U+2A6DF).
• 3..8 - Extensions C through H.
• 254 - CJK Compatibility Ideographs (U+F900..U+FAFF).

Examples

iex> Cldr.Collation.Han.block_index(0x4E00)
0

iex> Cldr.Collation.Han.block_index(0x3400)
1

Returns a specification to start this module under a supervisor.

See Supervisor.

@spec collation_elements(non_neg_integer()) :: [Cldr.Collation.Element.t()] | nil

Compute collation elements for a Han character using radical-stroke ordering.

Arguments

• codepoint - an integer codepoint for a CJK Unified Ideograph.

Returns

• [%Cldr.Collation.Element{}, %Cldr.Collation.Element{}] - two CEs encoding the radical-stroke key.
• nil - if the character has no radical data (falls back to implicit weights).

Examples

iex> Cldr.Collation.Han.ensure_loaded()
iex> elements = Cldr.Collation.Han.collation_elements(0x4E00)
iex> length(elements)
2

@spec compute_key(
  non_neg_integer(),
  non_neg_integer(),
  non_neg_integer(),
  non_neg_integer(),
  non_neg_integer()
) :: non_neg_integer()

Compute the 64-bit sorting key per UAX #38.

Bit layout:

• bits 52-63: unused (0).

• bits 44-51: radical number (1-214).

• bits 36-43: residual strokes.

• bits 32-35: reserved (0).

• bits 28-31: simplification level.

• bits 20-27: block index.

• bits 0-19: code point.

Arguments

• radical - the Kangxi radical number (1-214).
• residual_strokes - the residual stroke count after removing the radical.
• simplification - the simplification level (0 for traditional).
• block - the CJK block index (see block_index/1).
• codepoint - the Unicode codepoint.

Returns

A 64-bit integer encoding all components of the radical-stroke sort key.

Examples

iex> Cldr.Collation.Han.compute_key(1, 0, 0, 0, 0x4E00)
17592186064384

@spec ensure_loaded() :: :ok

Ensure the Han radical data is loaded into ETS.

Loads radical-stroke data from FractionalUCA.txt on first call. Subsequent calls are no-ops.

Returns

• :ok - the radical data is loaded and ready.

Examples

iex> Cldr.Collation.Han.ensure_loaded()
:ok

@spec key_to_elements(non_neg_integer()) :: [Cldr.Collation.Element.t()]

Convert a 64-bit radical-stroke key to two collation elements.

Encodes the key as two CEs using the Han implicit base (0xFB40):

• CE1: primary = 0xFB40 + (key >> 32), secondary = 0x0020, tertiary = 0x0002

• CE2: primary = (key & 0xFFFF) | 0x8000, secondary = 0x0000, tertiary = 0x0000

Arguments

• key - a 64-bit integer radical-stroke key from compute_key/5.

Returns

A list of two %Cldr.Collation.Element{} structs.

Examples

iex> elements = Cldr.Collation.Han.key_to_elements(0)
iex> Cldr.Collation.Element.primary(hd(elements))
0xFB40

@spec parse_radical_line(String.t()) ::
  {:ok, pos_integer(),
   [{non_neg_integer(), non_neg_integer(), non_neg_integer()}]}
  | :skip

Parse a radical definition line from FractionalUCA.txt.

Arguments

• line - a trimmed line from FractionalUCA.txt in the format [radical N=CANONICAL:MEMBER_LIST].

Returns

• {:ok, radical_num, members} - the radical number and a list of {codepoint, simplification, strokes} tuples.
• :skip - the line is not a radical definition.

Examples

iex> Cldr.Collation.Han.parse_radical_line("not a radical line")
:skip