Unicode.Age (Unicode v2.1.0)

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

The Age property records the version of Unicode in which a codepoint was first assigned. The value is an atom formed from the version number, for example :"1.1" or :"15.0".

The primary API is age/1 which returns the age of a codepoint, or the list of ages of a string. The functions fetch/1, get/1 and count/1 provide introspection of the codepoint ranges belonging to a given age.

Summary

Functions

age(string)

Returns the age of the given binary or codepoint.

ages()

Returns the map of Unicode ages.

aliases()

Returns a map of aliases for Unicode ages.

count(age)

Returns the count of the codepoints assigned in a given age.

fetch(age)

Returns the Unicode codepoint ranges for a given age.

get(age)

Returns the Unicode codepoint ranges for a given age.

known_ages()

Returns a list of known Unicode ages.

Functions

age(string)

Returns the age 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 age atom is returned. Unassigned codepoints return :unassigned.

  • For a binary, a list of the distinct ages of the codepoints in the binary is returned.

Examples

iex> Unicode.Age.age(?A)
:"1.1"

iex> Unicode.Age.age(0x0378)
:unassigned

ages()

Returns the map of Unicode ages.

Returns

  • A map where the age (as an atom version number) is the key and a list of codepoint ranges as 2-tuples is the value.

Examples

iex> Unicode.Age.ages() |> Map.get(:"1.1") |> hd()
{0, 501}

aliases()

Returns a map of aliases for Unicode ages.

An alias is an alternative name for referring to an age. PropertyValueAliases.txt gives each age a V<major>_<minor> alias, so "V18_0" is an alias for :"18.0". Alias keys are normalised by downcasing and removing whitespace and underscores, the same normalisation fetch/1 and get/1 apply to their argument, so "V18_0" is stored and looked up as "v180". Aliases are resolved by fetch/1 and get/1.

Returns

  • A map of age aliases to the canonical age name.

Examples

iex> Unicode.Age.aliases() |> Map.get("v11")
:"1.1"

iex> Unicode.Age.fetch("V18_0") == Unicode.Age.fetch("18.0")
true

count(age)

Returns the count of the codepoints assigned in a given age.

Arguments

  • age is any known age, as an atom or string.

Returns

  • A non-negative integer count of the codepoints in the age.

  • :error if the age is not known.

Examples

iex> Unicode.Age.count(:"1.1")
33979

fetch(age)

Returns the Unicode codepoint ranges for a given age.

Arguments

  • age is any known age, as an atom or string.

Returns

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

  • :error if the age is not known.

Examples

iex> Unicode.Age.fetch(:"1.1") |> elem(0)
:ok

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

get(age)

Returns the Unicode codepoint ranges for a given age.

Arguments

  • age is any known age, as an atom or string.

Returns

  • A list of codepoint ranges as 2-tuples.

  • nil if the age is not known.

Examples

iex> Unicode.Age.get(:"1.1") |> hd()
{0, 501}

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

known_ages()

Returns a list of known Unicode ages.

Returns

  • A list of atom version numbers.

Examples

iex> :"1.1" in Unicode.Age.known_ages()
true