collate

README

Collate

Collate is a simple collation library for comparing strings in various languages for Go. It's designed for the BuntDB project, and is simliar to the collation that is found in traditional database systems

The idea is that you call a function with a collation name and it generates a Less(a, b string) bool function that can be used for sorting using the sort package or with B-Tree style databases.

Install

go get -u github.com/admpub/collate

Example

// create a case-insensitive collation for spanish.
less := collate.IndexString("SPANISH_CI")
println(less("Hola", "hola"))
println(less("hola", "Hola"))
// Output:
// false
// false

Options

Case Sensitivity

Add _CI to the collation name to specify case-insensitive comparing.
Add _CS for case-sensitive compares, this is the default.

collate.Index("SPANISH_CI") // Case-insensitive collation for spanish
collate.Index("SPANISH_CS") // Case-sensitive collation for spanish

Loose Compares

Add _LOOSE to ignores diacritics, case and weight.

Numeric Compares

Add _NUM to specifies that numbers should sort numerically ("2" < "12")

JSON

You can also compare fields in json documents using the IndexJSON function. The GJSON is used under-the-hood.

var jsonA = `{"name":{"last":"Miller"}}`
var jsonB = `{"name":{"last":"anderson"}}`
less := collate.IndexJSON("ENGLISH_CI", "name.last")
println(less(jsonA, jsonB))
println(less(jsonB, jsonA))
// Output:
// false
// true

Supported Languages

Afrikaans Albanian AmericanEnglish Amharic Arabic Armenian Azerbaijani Bengali BrazilianPortuguese BritishEnglish Bulgarian Burmese CanadianFrench Catalan Chinese Croatian Czech Danish Dutch English Estonian EuropeanPortuguese EuropeanSpanish Filipino Finnish French Georgian German Greek Gujarati Hebrew Hindi Hungarian Icelandic Indonesian Italian Japanese Kannada Kazakh Khmer Kirghiz Korean Lao LatinAmericanSpanish Latvian Lithuanian Macedonian Malay Malayalam Marathi ModernStandardArabic Mongolian Nepali Norwegian Persian Polish Portuguese Punjabi Romanian Russian Serbian SerbianLatin SimplifiedChinese Sinhala Slovak Slovenian Spanish Swahili Swedish Tamil Telugu Thai TraditionalChinese Turkish Ukrainian Urdu Uzbek Vietnamese Zulu

Contact

Josh Baker @tidwall

License

Collate source code is available under the MIT License.

Documentation

Index

• func GetPreinited(lang string) func(a, b string) bool
• func IndexString(name string) (less func(a, b string) bool)
• func Less(a, b string) bool
• func MakeFuncLess(lang ...string) func(a, b string) bool
• func Preinit(langs ...string)
• func SortStrings(arr []string, lang ...string)
• func SupportedLangs() []string

Examples

• IndexString

Functions

func GetPreinited

func GetPreinited(lang string) func(a, b string) bool

func IndexString

func IndexString(name string) (less func(a, b string) bool)

IndexString returns a Less function that can be used to compare if string "a" is less than string "b". The "name" parameter should be a valid collate definition.

Examples of collation names
--------------------------------------------------------------------
ENGLISH, EN                -- English
AMERICANENGLISH, EN-US     -- English US
FRENCH, FR                 -- French
CHINESE, ZH                -- Chinese
SIMPLIFIEDCHINESE, ZH-HANS -- Simplified Chinese
...

Case insensitive: add the CI tag to the name
--------------------------------------------------------------------
ENGLISH_CI
FR_CI
ZH-HANS_CI
...

Case sensitive: add the CS tag to the name
--------------------------------------------------------------------
ENGLISH_CS
FR_CS
ZH-HANS_CS
...

For numerics: add the NUM tag to the name
Specifies that numbers should sort numerically ("2" < "12")
--------------------------------------------------------------------
DUTCH_NUM
JAPANESE_NUM
...

For loosness: add the LOOSE tag to the name
Ignores diacritics, case and weight
--------------------------------------------------------------------
JA_LOOSE
CHINESE_LOOSE
...

Example

var nameA = "Miller"
var nameB = "anderson"
less := IndexString("ENGLISH_CI")
fmt.Printf("%t\n", less(nameA, nameB))
fmt.Printf("%t\n", less(nameB, nameA))

Output:

false
true

func Less

func Less(a, b string) bool

func MakeFuncLess

func MakeFuncLess(lang ...string) func(a, b string) bool

func Preinit

func Preinit(langs ...string)

func SortStrings

func SortStrings(arr []string, lang ...string)

func SupportedLangs

func SupportedLangs() []string

SupportedLangs returns all of the languages that Index() supports.