is_chinese 1.0.3

//! # is_chinese
//!
//! detect whether a string is all Chinese
//!
//! ## example
//!
//! ```rust
//! use is_chinese;
//! assert!(is_chinese::is_chinese("中国"));
//! assert!(!is_chinese::is_chinese("ss"));
//! ```
//!

const CHINESE_RANGE: &[[u32; 2]] = &[
    // sequence is determine by occurrence probability
    [0x4e00, 0x9fff], // CJK Unified Ideographs
    // Chinese punctuation
    [0xff0c, 0xff0c],   //，
    [0x3002, 0x3002],   //。
    [0x00b7, 0x00b7],   //·
    [0x00d7, 0x00d7],   //×
    [0x2014, 0x2014],   //—
    [0x2018, 0x2018],   //‘
    [0x2019, 0x2019],   //’
    [0x201c, 0x201c],   //“
    [0x201d, 0x201d],   //”
    [0x2026, 0x2026],   //…
    [0x3001, 0x3001],   //、
    [0x300a, 0x300a],   //《
    [0x300b, 0x300b],   //》
    [0x300e, 0x300e],   //『
    [0x300f, 0x300f],   //』
    [0x3010, 0x3010],   //【
    [0x3011, 0x3011],   //】
    [0xff01, 0xff01],   //！
    [0xff08, 0xff08],   //（
    [0xff09, 0xff09],   //）
    [0xff1a, 0xff1a],   //：
    [0xff1b, 0xff1b],   //；
    [0xff1f, 0xff1f],   //？
    [0x3400, 0x4dbf],   // CJK Unified Ideographs Extension A
    [0x20000, 0x2a6df], // CJK Unified Ideographs Extension B
    [0x2a700, 0x2b73f], // CJK Unified Ideographs Extension C
    [0x2b740, 0x2b81f], // CJK Unified Ideographs Extension D
    [0x2b820, 0x2ceaf], // CJK Unified Ideographs Extension E
    [0x3300, 0x33ff],   // https://en.wikipedia.org/wiki/CJK_Compatibility
    [0xfe30, 0xfe4f],   // https://en.wikipedia.org/wiki/CJK_Compatibility_Forms
    [0xf900, 0xfaff],   // https://en.wikipedia.org/wiki/CJK_Compatibility_Ideographs
    [0x2f800, 0x2fa1f], // https://en.wikipedia.org/wiki/CJK_Compatibility_Ideographs_Supplement
];

///
/// ```
/// assert!(is_chinese::is_chinese("中国"));
/// ```
pub fn is_chinese(str: &str) -> bool {
    let has_ascii = str.chars().any(|c| c as u32 <= 255);

    if has_ascii {
        return false;
    }

    let is_all_chinese = str.chars().all(|c| {
        CHINESE_RANGE
            .iter()
            .any(|&[start, end]| c as u32 >= start && c as u32 <= end)
    });

    is_all_chinese
}