class ICU::Collator

• ICU::Collator
• Reference
• Object

Overview

Collation

This class allows to perform locale-sensitive string comparison.

Sort ordering may be customized by providing your own set of rules (see CLDR root sort order).

Usage

ICU::Collator.new("en").compare("y", "k") # => 1
ICU::Collator.new("lt").compare("y", "k") # => -1

col = ICU::Collator.new(rules: "&c < b < a")
col.compare("a", "b") # => 1
col.compare("b", "c") # => 1
col.compare("d", "e") # => -1

NOTE the #compare method requires ICU >= 50

See also

• ICU User Guide
• Reference C API
• Unit tests

Defined in:

Constant Summary

DEFAULT = AttributeValue::Default

KEYWORDS = begin keywords = Hash(String, Set(String)).new ustatus = LibICU::UErrorCode::UZeroError kenum = LibICU.ucol_get_keywords(pointerof(ustatus)) ICU.check_error!(ustatus) (UEnum.new(kenum, owns: true)).each do |keyword| ustatus = LibICU::UErrorCode::UZeroError venum = LibICU.ucol_get_keyword_values(keyword, pointerof(ustatus)) ICU.check_error!(ustatus) keywords[keyword] = Set(String).new((UEnum.new(venum, owns: true)).to_a) end keywords end

LOCALES = begin ustatus = LibICU::UErrorCode::UZeroError uenum = LibICU.ucol_open_available_locales(pointerof(ustatus)) ICU.check_error!(ustatus) Set(String).new((UEnum.new(uenum, owns: true)).to_a) end

OFF = AttributeValue::Off

ON = AttributeValue::On

Constructors

• .new(locale : String | Nil = nil, rules : String | Nil = nil, normalization_mode : AttributeValue = DEFAULT, strength : Strength = AttributeValue::DefaultStrength)

  Initialize a new Collator specifying a locale or a set of rules.

Class Method Summary

• .functional_equivalent(locale : String, keyword : String = KEYWORDS.keys.first)

  Returns a functional equivalent to a given locale

Instance Method Summary

• #[](attribute : Attribute) : AttributeValue

  Get the value of the specified attribute

• #[]=(attribute : Attribute, value : AttributeValue)

  Set a value to the specified attribute

• #compare(s1 : String, s2 : String) : Int

  Compares two strings

• #contractions : Set(Char)

  Returns the set of contraction characters defined by this collator.

• #contractions_and_expansions(add_prefixes : Bool = false) : Tuple(Set(Char), Set(Char))

  Returns the contraction and expansion character sets for this collator.

• #equals?(s1 : String, s2 : String) : Bool

  Returns true if the two strings are equivalent

• #finalize
• #locale : String?
• #reorder_codes : Array(ReorderCode)
• #reorder_codes=(codes : Array(ReorderCode))
• #rules : String?
• #strength : Strength
• #strength=(value : Strength)
• #tailored_set : Set(Char)

  Returns the set of characters that are tailored (customized) by this collator relative to the root collation order.

• #to_unsafe : LibICU::UCollator

Constructor Detail

ICU::Collator.new
ICU::Collator.new("pt")
ICU::Collator.new(locale: "lt")
ICU::Collator.new(rules: "&c < b < a")

Class Method Detail

ICU::Collator.functional_equivalent("en") # => "root"

Instance Method Detail

ICU::Collator.new("en").compare("y", "k")       # => 1
ICU::Collator.new("lt").compare("y", "k")       # => -1
ICU::Collator.new("fr").compare("côte", "coté") # => -1

col = ICU::Collator.new("cs")   # Czech has "ch" as a contraction
col.contractions.includes?('c') # => true

conts, exps = ICU::Collator.new("cs").contractions_and_expansions
conts.includes?('c') # => true

col = ICU::Collator.new(rules: "&a = b")
col.equals?("a", "b") # => true

col = ICU::Collator.new(rules: "&b < a")
col.tailored_set.includes?('a') # => true
col.tailored_set.includes?('b') # => true