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+# IntlMemoizer
+
+`intl-memoizer` is a crate designed to handle lazy-initialized references
+to intl formatters.
+
+The assumption is that allocating a new formatter instance is costly, and such
+instance is read-only during its life time, with constructor being expensive, and
+`format`/`select` calls being cheap.
+
+In result it pays off to use a singleton to manage memoization of all instances of intl
+APIs such as `PluralRules`, DateTimeFormat` etc. between all `FluentBundle` instances.
+
+Usage
+-----
+
+```rust
+use intl_memoizer::{IntlMemoizer, Memoizable};
+use unic_langid::langid;
+
+use intl_pluralrules::{PluralRules, PluralRuleType, PluralCategory};
+
+impl Memoizable for PluralRules {
+    type Args = (PluralRulesType,);
+    fn construct(lang: LanguageIdentifier, args: Self::Args) -> Self {
+      Self::new(lang, args.0)
+    }
+}
+
+fn main() {
+    let lang = langid!("en-US");
+
+    // A single memoizer for all languages
+    let mut memoizer = IntlMemoizer::new();
+
+    // A RefCell for a particular language to be used in all `FluentBundle`
+    // instances.
+    let mut en_us_memoizer = memoizer.get_for_lang(lang.clone());
+
+    // Per-call borrow
+    let mut en_us_memoizer_borrow = en_us_memoizer.borrow_mut();
+    let cb = en_us_memoizer_borrow.get::<PluralRules>((PluralRulesType::Cardinal,));
+    assert_eq!(cb.select(1), PluralCategory::One);
+}
+
+```
+
+Get Involved
+------------
+
+`fluent-rs` is open-source, licensed under the Apache License, Version 2.0.  We
+encourage everyone to take a look at our code and we'll listen to your
+feedback.
+
+
+Discuss
+-------
+
+We'd love to hear your thoughts on Project Fluent! Whether you're a localizer
+looking for a better way to express yourself in your language, or a developer
+trying to make your app localizable and multilingual, or a hacker looking for
+a project to contribute to, please do get in touch on the mailing list and the
+IRC channel.
+
+ - Discourse: https://discourse.mozilla.org/c/fluent
+ - IRC channel: [irc://irc.mozilla.org/l20n](irc://irc.mozilla.org/l20n)