intl 0.1.3

Pure-Rust, no_std internationalization primitives (a pure-Rust ICU analog). The `unicode` module provides General_Category, character predicates, scripts, East Asian Width, numeric values, case mapping/folding, UAX #15 normalization (NFC/NFD/NFKC/NFKD), and UTS #10 collation — property tables compiled into const-fn match lookups, with feature-selectable codepoint ranges.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85

//! The Unicode `Numeric_Type` and `Numeric_Value` properties.

use super::generated::numeric as gen;

/// The kind of numeric value a codepoint carries (`Numeric_Type`).
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[repr(u8)]
pub enum NumericType {
    /// `Decimal` — a decimal digit usable in positional notation (`Nd`); the
    /// value is always an integer `0..=9`.
    Decimal,
    /// `Digit` — a standalone digit (e.g. superscripts), integer `0..=9`.
    Digit,
    /// `Numeric` — any other numeric value, including fractions and large CJK
    /// number ideographs.
    Numeric,
}

/// An exact Unicode `Numeric_Value`, as a rational `numerator / denominator`.
///
/// Most codepoints are integers (`denominator == 1`); vulgar fractions such as
/// `½` use a larger denominator. The value may be negative.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub struct NumericValue {
    /// The signed numerator.
    pub numerator: i64,
    /// The positive denominator (`1` for integers).
    pub denominator: u32,
}

impl NumericValue {
    /// `true` if the value is an integer (denominator `1`).
    #[inline]
    #[must_use]
    pub const fn is_integer(self) -> bool {
        self.denominator == 1
    }

    /// The integer value, or `None` if it is a proper fraction.
    #[inline]
    #[must_use]
    pub const fn to_i64(self) -> Option<i64> {
        if self.denominator == 1 {
            Some(self.numerator)
        } else {
            None
        }
    }

    /// The value as an `f64`.
    #[inline]
    #[must_use]
    pub fn as_f64(self) -> f64 {
        self.numerator as f64 / f64::from(self.denominator)
    }
}

/// The [`NumericType`] of `c`, or `None` if `c` has no numeric value.
#[inline]
#[must_use]
pub const fn numeric_type(c: char) -> Option<NumericType> {
    gen::numeric_type(c as u32)
}

/// The exact [`NumericValue`] of `c`, or `None` if `c` has no numeric value.
///
/// # Examples
/// ```
/// use intl::unicode::numeric_value;
/// assert_eq!(numeric_value('7').unwrap().to_i64(), Some(7));
/// assert_eq!(numeric_value('½').unwrap().as_f64(), 0.5);
/// assert_eq!(numeric_value('A'), None);
/// ```
#[inline]
#[must_use]
pub const fn numeric_value(c: char) -> Option<NumericValue> {
    gen::numeric_value(c as u32)
}

/// The [`NumericValue`] of an arbitrary Unicode scalar value.
#[inline]
#[must_use]
pub const fn numeric_value_u32(cp: u32) -> Option<NumericValue> {
    gen::numeric_value(cp)
}