# Unicode
[](https://hex.pm/packages/unicode)
[](https://hex.pm/packages/unicode)
[](https://hex.pm/packages/unicode)
[](https://hex.pm/packages/unicode)
Functions to return information about Unicode codepoints.
Elixir strings are UTF-8-encoded [Unicode](https://unicode.org) binaries. This is a flexible and complete encoding scheme for the worlds many scripts, characters and emjois. However since it's a variable length encoding (using between one and four bytes for UTF-8) it is harder to use high-performance byte-oriented functions to decompose strings.
Since checking strings and codepoints for certain attributes - like whether they are upper case, or symbols, or whitespace - is a common occurrence, a performant approach to such detection is useful.
It is tempting to assume the use of [US ASCII](https://en.wikipedia.org/wiki/ASCII) encoding and checking only for characters in that range. For example it is very common to see code in Elixir checking `codepoint in ?a..?z` to check for lowercase alphabetic characters. When the underlying programming language has no canonical form for a string beyond bytes this may be considered acceptable - the programmer is defining the script domain as he or she sees fit.
However since Elixir strings are declared to be [UTF-8 encoded Unicode strings](https://unicode.org/faq/utf_bom.html#utf8-1) it seems appropriate to make it easier to determine the characteristics of codepoints (and strings) using this standard.
The Elixir standard library does not provide introspection beyond that required to support casing (String.downcase/1, String.upcase/1, String.capitalize/1). This library aims to *fill in the blanks* a little bit.
### Unicode version
As of [unicode version 1.20.0](https://hex.pm/packages/unicode/1.20.0) published on September 11th, 2024, [Unicode 16.0](https://www.unicode.org/versions/Unicode16.0.0/) forms the underlying data.
## Additional Unicode libraries
[ex_unicode](https://hex.pm/packages/unicode) provides basic introspection of Unicode codepoints and strings. Additional libraries (either released or in development) build upon this library):
* [unicode_set](https://github.com/elixir-unicode/unicode_set) implements functions to parse and match on [unicode sets](http://unicode.org/reports/tr35/#Unicode_Sets)
* [unicode_guards](https://github.com/elixir-unicode/unicode_guards) is a simple library implementing common function guards using `unicode_set` and `unicode`
* [unicode_string](https://github.com/elixir-unicode/unicode_string) is a library to implement efficient string splitting into words and sentences based upon the [Unicode Segementation](https://unicode.org/reports/tr29/) algorithm.
* [unicode_transform](https://github.com/elixir-unicode/unicode_transform) implements the [Unicode transform](https://unicode.org/reports/tr35/tr35-general.html#Transforms) specification.
## Unicode Functions
The following is a partial list of functions included in the library. See the documentation for the relevant module for further information:
### Codepoint ranges
These functions return the codepoints as list of 2-tuples for the given property:
* `Unicode.Block.blocks/0`
* `Unicode.Script.scripts/0`
* `Unicode.GeneralCategory.categories/0`
* `Unicode.CombiningClass.combining_classes/0`
* `Unicode.GraphemeBreak.grapheme_breaks/0`
* `Unicode.LineBreak.line_breaks/0`
* `Unicode.SentenceBreak.sentence_breaks/0`
* `Unicode.IndicSyllabicCategory.indic_syllabic_categories/0`
* `Unicode.Property.properties/0`
### Introspection of codepoints and strings
The following functions return the block, script and category for codepoints and strings:
* `Unicode.script/1`
```elixir
iex> Unicode.script ?ä
:latin
iex> Unicode.script ?خ
:arabic
iex> Unicode.script ?अ
:devanagari
```
* `Unicode.block/1`
```elixir
iex> Unicode.block ?ä
:latin_1_supplement
iex> Unicode.block ?A
:basic_latin
iex> Unicode.block "äA"
[:latin_1_supplement, :basic_latin]
```
* `Unicode.category/1`
```elixir
iex> Unicode.category ?ä
:Ll
iex> Unicode.category ?A
:Lu
iex> Unicode.category ?🧐
:So
```
* `Unicode.properties/1`
```elixir
iex> Unicode.properties 0x1bf0
[
:alphabetic,
:case_ignorable,
:grapheme_extend,
:id_continue,
:other_alphabetic,
:xid_continue
]
iex> Unicode.properties ?A
[
:alphabetic,
:ascii_hex_digit,
:cased,
:changes_when_casefolded,
:changes_when_casemapped,
:changes_when_lowercased,
:grapheme_base,
:hex_digit,
:id_continue,
:id_start,
:uppercase,
:xid_continue,
:xid_start
]
iex> Unicode.properties ?+
[:grapheme_base, :math, :pattern_syntax]
iex> Unicode.properties "a1+"
[
[
:alphabetic,
:ascii_hex_digit,
:cased,
:changes_when_casemapped,
:changes_when_titlecased,
:changes_when_uppercased,
:grapheme_base,
:hex_digit,
:id_continue,
:id_start,
:lowercase,
:xid_continue,
:xid_start
],
[
:ascii_hex_digit,
:emoji,
:grapheme_base,
:hex_digit,
:id_continue,
:xid_continue
],
[:grapheme_base, :math, :pattern_syntax]
]
```
### Character classes
These functions help filter codepoints and strings based upon their properties. They return a boolean result.
* `Unicode.alphabetic?/1`
* `Unicode.alphanumeric?/1`
* `Unicode.digits?/1`
* `Unicode.numeric?/1`
* `Unicode.emoji?/1`
* `Unicode.math?/1`
* `Unicode.cased?/1`
* `Unicode.lowercase?/1`
* `Unicode.uppercase?/1`
Any known property can be called as a function `Unicode.Property.<property_name>(codepoint_or_string)` or `Unicode.Property.<property_name>?(codepoint_or_string)` to return a boolean.
### Transformations
The function `Unicode.unaccent/1` attempts to transform a Unicode string into a subset of the Latin-1 alphabet by removing diacritical marks from text. It is not a full transformation (which will be available in the upcoming `unicode_transform` library.)
## Recognition
The information functions are heavily inspired by [@qqwy's elixir-unicode package](https://github.com/Qqwy/elixir-unicode) and compatibility with some of the api is represented by including some of the doctests from that package. Originally published under the `:unicode` package name on hex, this original work is now replaced with this library code.
## Installation
The package can be installed by adding `unicode` to your list of dependencies in `mix.exs`:
<!-- BEGIN: VERSION -->
```elixir
def deps do
[
{:unicode, "~> 1.20"}
]
end
```
<!-- END: VERSION -->
The docs can be found at [https://hexdocs.pm/unicode](https://hexdocs.pm/unicode).
