# `Unicode.JoiningGroup`
[🔗](https://github.com/elixir-unicode/unicode/blob/v2.2.0/lib/unicode/property/joining_group.ex#L1)

Functions to introspect the Unicode `Joining_Group` property for binaries (Strings) and codepoints.

The `Joining_Group` property groups Arabic and Syriac letters that share the same shaping behaviour, for example `:beh`, `:alaph` or `:teh_marbuta`. Codepoints that are not cursively joined have the value `:no_joining_group`.

The primary API is `joining_group/1` which returns the joining group of a codepoint, or the list of joining groups of a string. This complements `Unicode.JoiningType`.

# `aliases`

Returns a map of aliases for Unicode joining groups.

### Returns

* A map where the alias string is the key and the joining group is the value.

### Examples

    iex> Unicode.JoiningGroup.aliases() |> Map.get("beh")
    :beh

# `count`

Returns the count of the codepoints in a given joining group.

Aliases are resolved by this function.

### Arguments

* `joining_group` is any joining group name or alias, as an atom or string.

### Returns

* A non-negative integer count of the codepoints in the joining group.

* `:error` if the joining group is not known.

### Examples

    iex> is_integer(Unicode.JoiningGroup.count(:beh))
    true

# `fetch`

Returns the Unicode codepoint ranges for a given joining group.

Aliases are resolved by this function.

### Arguments

* `joining_group` is any joining group name or alias, as an atom or string.

### Returns

* `{:ok, range_list}` where `range_list` is a list of codepoint ranges as 2-tuples.

* `:error` if the joining group is not known.

### Examples

    iex> Unicode.JoiningGroup.fetch(:beh) |> elem(0)
    :ok

    iex> Unicode.JoiningGroup.fetch(:invalid)
    :error

# `get`

Returns the Unicode codepoint ranges for a given joining group.

Aliases are resolved by this function.

### Arguments

* `joining_group` is any joining group name or alias, as an atom or string.

### Returns

* A list of codepoint ranges as 2-tuples.

* `nil` if the joining group is not known.

### Examples

    iex> Unicode.JoiningGroup.get(:invalid)
    nil

# `joining_group`

Returns the joining group of the given binary or codepoint.

### Arguments

* `string_or_codepoint` is either a binary (String) or a codepoint in the range `0..0x10FFFF`.

### Returns

* For a codepoint, a single joining group atom is returned. Codepoints that are not cursively joined return `:no_joining_group`.

* For a binary, a list of the distinct joining groups of the codepoints in the binary is returned.

### Examples

    iex> Unicode.JoiningGroup.joining_group(0x0628)
    :beh

    iex> Unicode.JoiningGroup.joining_group(?A)
    :no_joining_group

# `joining_groups`

Returns the map of Unicode joining groups.

### Returns

* A map where the joining group is the key and a list of codepoint ranges as 2-tuples is the value.

### Examples

    iex> :beh in Map.keys(Unicode.JoiningGroup.joining_groups())
    true

# `known_joining_groups`

Returns a list of known Unicode joining group names.

### Returns

* A list of atom joining group names.

### Examples

    iex> :alaph in Unicode.JoiningGroup.known_joining_groups()
    true

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*Consult [api-reference.md](api-reference.md) for complete listing*