Determine the bidirectional character type of a character.

This is used to initialize the Unicode bidirectional algorithm, published in UAX #9.

There are several blocks of unassigned code points which are reserved to specific script blocks and therefore return a specific bidirectional character type. For example, unassigned code point ﹵, in the Arabic block, has type “AL”.

If not specifically assigned or reserved, the default value is “L” (Left-to-Right).

This is sourced from DerivedBidiClass.txt

Examples

iex> UnicodeData.bidi_class("A")
"L"
iex> UnicodeData.bidi_class("د")
"AL"
iex> UnicodeData.bidi_class("𐭀")
"R"
iex> UnicodeData.bidi_class("﹵")
"AL"

The Bidi_Mirroring_Glyph property returns the character suitable for character-based mirroring, if one exists. Otherwise, it returns nil.

Character-based mirroring is used by the Unicode bidirectional algorithm. A layout engine may want to consider other method of mirroring.

This is sourced from BidiMirroring.txt

Examples

iex> UnicodeData.bidi_mirror_codepoint("[")
"]"
iex> UnicodeData.bidi_mirror_codepoint("A")
nil

The Bidi_Mirrored property indicates whether or not there is another Unicode character that typically has a glyph that is the mirror image of the original character’s glyph.

Character-based mirroring is used by the Unicode bidirectional algorithm. A layout engine may want to consider other method of mirroring.

Some characters like ∛ (CUBE ROOT) claim to be mirrored but do not actually have a corresponding mirror character - in those cases this function returns false.

This is sourced from BidiMirroring.txt

Examples

iex> UnicodeData.bidi_mirrored?("A")
false
iex> UnicodeData.bidi_mirrored?("[")
true
iex> UnicodeData.bidi_mirrored?("∛")
false

The Bidi_Paired_Bracket property is used to establish pairs of opening and closing brackets for the purposes of the Unicode bidirectional algorithm.

If a character is an opening or closing bracket, this will return the other character in the pair. Otherwise, it returns nil.

For example

This is sourced from BidiBrackets.txt

Examples

iex> UnicodeData.bidi_paired_bracket("[")
"]"
iex> UnicodeData.bidi_paired_bracket("]")
"["
iex> UnicodeData.bidi_paired_bracket("A")
nil

The Unicode Bidi_Paired_Bracket_Type property classifies characters into opening and closing paired brackets for the purposes of the Unicode bidirectional algorithm.

It returns one of the following values:

• o Open - The character is classified as an opening bracket.
• c Close - The character is classified as a closing bracket.
• n None - the character is not a paired bracket character.

This is sourced from BidiBrackets.txt

Examples

iex> UnicodeData.bidi_paired_bracket_type("[")
"o"
iex> UnicodeData.bidi_paired_bracket_type("}")
"c"
iex> UnicodeData.bidi_paired_bracket_type("A")
"n"

Determine the joining group for cursive scripts.

Characters from other scripts return No_Joining_Group as they do not participate in cursive shaping.

The ALAPH and DALATH RISH joining groups are of particular interest to shaping engines dealing with Syriac. Chapter 9.3 of the Unicode Standard discusses Syriac shaping in detail.

This is sourced from ArabicShaping.txt

Examples

iex> UnicodeData.joining_group("ك")
"KAF"
iex> UnicodeData.joining_group("د")
"DAL"
iex> UnicodeData.joining_group("ܐ")
"ALAPH"

Determine the joining type for cursive scripts.

Cursive scripts have the following join types:

• R Right_Joining (top-joining for vertical)
• L Left_Joining (bottom-joining for vertical)
• D Dual_Joining
• C Join_Causing
• U Non_Joining
• T Transparent

Characters from other scripts return U as they do not participate in cursive shaping.

This is sourced from ArabicShaping.txt

Examples

iex> UnicodeData.joining_type("ك")
"D"
iex> UnicodeData.joining_type("د")
"R"
iex> UnicodeData.joining_type("ܐ")
"R"

Determine if the script is written right-to-left.

This data is derived from ISO 15924. There’s a handy sortable table on the Wikipedia page for ISO 15924.

Examples

iex> UnicodeData.right_to_left?("Latin")
false
iex> UnicodeData.right_to_left?("Arabic")
true

You can also pass the script short name.

iex> UnicodeData.right_to_left?("adlm")
true

Lookup the script property associated with a codepoint.

This will return the script property value. In addition to the explicitly defined scripts, there are three special values.

• Characters with script value Inherited inherit the script of the preceding character.
• Characters with script value Common are used in multiple scripts.
• Characters of Unknown script are unassigned, private use, noncharacter or surrogate code points.

This is sourced from Scripts.txt

Examples

iex> UnicodeData.script_from_codepoint("a")
"Latin"
iex> UnicodeData.script_from_codepoint("9")
"Common"
iex> UnicodeData.script_from_codepoint("ك")
"Arabic"

Get the short name associated with a script. This is the tag used to identify scripts in OpenType fonts and generally matches the script code defined in ISO 15942.

See Annex #24 for more about the relationship between Unicode and ISO 15942.

Data from OpenType script tags and PropertyValueAliases.txt

Examples

iex> UnicodeData.script_to_tag("Latin")
"latn"
iex> UnicodeData.script_to_tag("Unknown")
"zzzz"
iex> UnicodeData.script_to_tag("Adlam")
"adlm"

Determine if a script uses the Joining Type property to select contextual forms.

Typically this is used to select a shaping engine, which will then call joining_type/1 and joining_group/1 to do cursive shaping.

Examples

iex> UnicodeData.uses_joining_type?("Latin")
false
iex> UnicodeData.uses_joining_type?("Arabic")
true
iex> UnicodeData.uses_joining_type?("Nko")
true

You can also pass the script short name.

iex> UnicodeData.uses_joining_type?("syrc")
true