lens
lens
A multiformat internationalization (i18n) shard for Crystal.
There is no doubt that the crystal community lacks many essential features that most modern day languages have; one of which is internationalization. Lens is an attempt to fix that.
Getting started
Lens supports numerous different formats:
- GNU Gettext (
Gettext::POBackend
,Gettext::MOBackend
)- You can use both .po and .mo
- Crystal-i18n (
CrystalI18n::I18n
)- Stored under .yml
- More coming soon
To get started, you should select one that fits your needs the best. See here for information regarding them.
Each backend can then be initialized with the locale directory
backend = Gettext::MOBackend.new("locales")
Each backend also supports nested directories and multiple files of the same language.
GNU Gettext
The GNU project's implementation of Gettext
backend = Gettext::MOBackend.new("locales")
catalogue_hash = backend.create() # => LanguageCode|| Filename => Catalogue
catalogue = catalogue_hash["en_US"]
For detailed information regarding usage please refer to the actual API documentation. A brief overview of the functionality is present below.
Basic usage
Messages are fetched with the gettext
method. If it doesn't exist then the given ID would be returned.
catalogue.gettext("A message") # => "Translated message"
catalogue.gettext("I don't exist") # => "I don't exist"
Pluralization
Pluralization is done through the ngettext
method. The given number is parsed through the C expression from the Plural-Forms header to know which plural-form to use.
catalogue.ngettext("I have %d apple", "I have %d apples", 0) # => "Translated I have %d apple"
catalogue.ngettext("I have %d apple", "I have %d apples", 1) # => "Translated I have %d apples"
Context
Key can be constrained by a specific context and is accessed through the pgettext method.
catalogue.pgettext("CopyPasteMenu", "copy") # => "Translated copy"
catalogue.pgettext("CopyPasteMenu", "I don't exist") # => "I don't exist"
Context with pluralization
Context-constrained messages can also have plural-forms and is accessed through the npgettext
method
catalogue.npgettext("CopyPasteMenu", "Export %d file", "Export %d files", 0) # => "Translated message with plural-form 1"
catalogue.npgettext("CopyPasteMenu", "Export %d file", "Export %d files", 1) # => "Translated message with plural-form 0"
Crystal-i18n
Is a format based on ruby-yml similar to what many others in the crystal community has implemented.
# The backend is the catalogue in the case of crystal-i18n
catalogue = CrystalI18n::I18n.new("locales")
Each file should be named like language-code.yml
For detailed information regarding usage please refer to the actual API documentation. A brief overview of the functionality is present below.
Basic usage
catalogue.translate("en", "translation") # => "Translated Message"
Nested keys can be accessed by separating routes with .
catalogue.translate("en", "nested_key.forth.forth-third.forth-third-fifth.4344")
Pluralization
catalogue.translate("en", "possessions.fruits.apples", 50) # => "I have 50 apples"
catalogue.translate("en", "possessions.fruits.apples", 1) # => "I have 1 apple"
Plural-rules follows CLDR and is pre-defined in lens for many languages. If your language isn't included in lens you many define (or even overwrite) a new plural-rule through the CrystalI18n.define_rule
method
CrystalI18n.define_rule("ar", ->(n : Int32 | Int64 | Float64) {
case
when n == 0 then "zero"
when n == 1 then "one"
when n == 2 then "two"
when 3..10 === n % 100 then "few"
when 11..99 === n % 100 then "many"
else "other"
end
})
Interpolation
Interpolation is done through keyword arguments in the #translate
method
# message is 'Hello there, my name is %{name} and I'm a %{profession}`.
result = catalogue.translate("en", "introduction.messages", name: "Steve", profession: "programmer")
result # => "Hello there, my name is Steve and I'm a programmer"
Iteration
If the value at the given path (key) turns out to be an array then you can pass in the iter argument to select a specific value at the given index
catalogue.translate("en", "items.foods", iter: 2) # => "Hamburger"
API documentation
Installation
-
Add the dependency to your
shard.yml
:dependencies: lens: github: syeopite/lens
-
Run
shards install
Contributing
- Fork it (https://github.com/syeopite/lens/fork)
- Create your feature branch (
git checkout -b my-new-feature
) - Commit your changes (
git commit -am 'Add some feature'
) - Push to the branch (
git push origin my-new-feature
) - Create a new Pull Request
Contributors
- syeopite - creator and maintainer