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// This file is part of ICU4X. For terms of use, please see the file
// called LICENSE at the top level of the ICU4X source tree
/// A macro allowing for compile-time construction of valid [`LanguageIdentifier`]s.
///
/// The macro will perform syntax canonicalization of the tag.
///
/// # Examples
///
/// ```
/// use icu::locid::{langid, LanguageIdentifier};
///
/// const DE_AT: LanguageIdentifier = langid!("de_at");
///
/// let de_at: LanguageIdentifier = "de_at".parse().unwrap();
///
/// assert_eq!(DE_AT, de_at);
/// ```
///
/// *Note*: The macro cannot produce language identifiers with more than one variants due to const
/// limitations (see [`Heap Allocations in Constants`]):
///
/// ```compile_fail,E0080
/// icu::locid::langid!("und-variant1-variant2");
/// ```
///
/// Use runtime parsing instead:
/// ```
/// "und-variant1-variant2"
/// .parse::<icu::locid::LanguageIdentifier>()
/// .unwrap();
/// ```
///
/// [`LanguageIdentifier`]: crate::LanguageIdentifier
#[macro_export]
macro_rules! langid {
($langid:literal) => {{
const R: $crate::LanguageIdentifier =
match $crate::LanguageIdentifier::try_from_bytes_with_single_variant($langid.as_bytes()) {
Ok((language, script, region, variant)) => $crate::LanguageIdentifier {
language,
script,
region,
variants: match variant {
Some(v) => $crate::subtags::Variants::from_variant(v),
None => $crate::subtags::Variants::new(),
}
},
#[allow(clippy::panic)] // const context
_ => panic!(concat!("Invalid language code: ", $langid, " . Note langid! macro can only support up to a single variant tag. Use runtime parsing instead.")),
};
R
}};
}
/// A macro allowing for compile-time construction of valid [`Locale`]s.
///
/// The macro will perform syntax canonicalization of the tag.
///
/// # Examples
///
/// ```
/// use icu::locid::{locale, Locale};
///
/// const DE_AT: Locale = locale!("de_at");
///
/// let de_at: Locale = "de_at".parse().unwrap();
///
/// assert_eq!(DE_AT, de_at);
/// ```
///
/// *Note*: The macro cannot produce locales with more than one variant or multiple extensions
/// (only single keyword unicode extension is supported) due to const
/// limitations (see [`Heap Allocations in Constants`]):
///
/// ```compile_fail,E0080
/// icu::locid::locale!("sl-IT-rozaj-biske-1994");
/// ```
/// Use runtime parsing instead:
/// ```
/// "sl-IT-rozaj-biske-1994"
/// .parse::<icu::locid::Locale>()
/// .unwrap();
/// ```
///
/// Locales with multiple keys are not supported
/// ```compile_fail,E0080
/// icu::locid::locale!("th-TH-u-ca-buddhist-nu-thai");
/// ```
/// Use runtime parsing instead:
/// ```
/// "th-TH-u-ca-buddhist-nu-thai"
/// .parse::<icu::locid::Locale>()
/// .unwrap();
/// ```
///
/// Locales with attributes are not supported
/// ```compile_fail,E0080
/// icu::locid::locale!("en-US-u-foobar-ca-buddhist");
/// ```
/// Use runtime parsing instead:
/// ```
/// "en-US-u-foobar-ca-buddhist"
/// .parse::<icu::locid::Locale>()
/// .unwrap();
/// ```
///
/// Locales with single key but multiple types are not supported
/// ```compile_fail,E0080
/// icu::locid::locale!("en-US-u-ca-islamic-umalqura");
/// ```
/// Use runtime parsing instead:
/// ```
/// "en-US-u-ca-islamic-umalqura"
/// .parse::<icu::locid::Locale>()
/// .unwrap();
/// ```
/// [`Locale`]: crate::Locale
#[macro_export]
macro_rules! locale {
($locale:literal) => {{
const R: $crate::Locale =
match $crate::Locale::try_from_bytes_with_single_variant_single_keyword_unicode_extension(
$locale.as_bytes(),
) {
Ok((language, script, region, variant, keyword)) => $crate::Locale {
id: $crate::LanguageIdentifier {
language,
script,
region,
variants: match variant {
Some(v) => $crate::subtags::Variants::from_variant(v),
None => $crate::subtags::Variants::new(),
},
},
extensions: match keyword {
Some(k) => $crate::extensions::Extensions::from_unicode(
$crate::extensions::unicode::Unicode {
keywords: $crate::extensions::unicode::Keywords::new_single(
k.0,
$crate::extensions::unicode::Value::from_tinystr(k.1),
),
attributes: $crate::extensions::unicode::Attributes::new(),
},
),
None => $crate::extensions::Extensions::new(),
},
},
#[allow(clippy::panic)] // const context
_ => panic!(concat!(
"Invalid language code: ",
$locale,
" . Note the locale! macro only supports up to one variant tag; \
unicode extensions are not supported. Use \
runtime parsing instead."
)),
};
R
}};
}
#[cfg(test)]
mod test {
use crate::LanguageIdentifier;
use crate::Locale;
#[test]
fn test_langid_macro_can_parse_langid_with_single_variant() {
const DE_AT_FOOBAR: LanguageIdentifier = langid!("de_at-foobar");
let de_at_foobar: LanguageIdentifier = "de_at-foobar".parse().unwrap();
assert_eq!(DE_AT_FOOBAR, de_at_foobar);
}
#[test]
fn test_locale_macro_can_parse_locale_with_single_variant() {
const DE_AT_FOOBAR: Locale = locale!("de_at-foobar");
let de_at_foobar: Locale = "de_at-foobar".parse().unwrap();
assert_eq!(DE_AT_FOOBAR, de_at_foobar);
}
#[test]
fn test_locale_macro_can_parse_locale_with_single_keyword_unicode_extension() {
const DE_AT_U_CA_FOOBAR: Locale = locale!("de_at-u-ca-foobar");
let de_at_u_ca_foobar: Locale = "de_at-u-ca-foobar".parse().unwrap();
assert_eq!(DE_AT_U_CA_FOOBAR, de_at_u_ca_foobar);
}
}