devela 0.27.0

A development layer of coherence.
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
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246

// devela::text::char::digits::usize

use super::*;
use crate::{Cmp, StringU8, TextLut, is};

impl Digits<usize> {
    /// The maximum number of decimal digits a `usize` can represent in the current platform.
    pub const MAX_DIGITS_10: u8 = Digits(usize::MAX).count_digits10();

    /// The maximum number of hexadecimal digits a `usize` can represent in the current platform.
    pub const MAX_DIGITS_16: u8 = Digits(usize::MAX).count_digits16();

    #[doc = DOC_COUNT_DIGITS_10!()]
    /// # Example
    /// ```
    /// # use devela::text::Digits;
    /// assert_eq![1, Digits(0_usize).count_digits10()];
    /// assert_eq![4, Digits(9876_usize).count_digits10()];
    /// ```
    #[must_use]
    pub const fn count_digits10(self) -> u8 {
        is![self.0 == 0, 1, self.0.ilog10() as u8 + 1]
    }
    #[doc = DOC_COUNT_DIGITS_16!()]
    #[must_use]
    pub const fn count_digits16(self) -> u8 {
        is![self.0 == 0, 1, ((self.0.ilog2() + 4) / 4) as u8]
    }

    /* digit_at_ */

    /// Returns the ASCII decimal digit at the specified index.
    ///
    /// Returns `b'0'` if the index is beyond the number's decimal digits.
    #[must_use]
    #[inline(always)]
    pub const fn digit_at_index10(self, index: u8) -> u8 {
        is![index >= self.count_digits10(), return b'0'];
        let power = TextLut::POWERS10[index as usize] as usize;
        (self.0 / power % 10) as u8 + b'0'
    }

    /// Returns the ASCII decimal digit at the specified index.
    ///
    /// Returns `None` if the index is beyond the number's decimal digits.
    #[must_use]
    pub const fn digit_at_index10_checked(self, index: u8) -> Option<u8> {
        is![index >= self.count_digits10(), return None];
        let power = TextLut::POWERS10[index as usize] as usize;
        Some((self.0 / power % 10) as u8 + b'0')
    }

    /// Returns the ASCII hexadecimal digit at the specified index (0 = least significant digit).
    ///
    /// For indices beyond the number's hexadecimal digits, returns the digit `b'0'`.
    #[must_use]
    pub const fn digit_at_index16(self, index: u8) -> u8 {
        let shift = index as u32 * 4;
        let digit = self.0.unbounded_shr(shift) & 0xF;
        TextLut::DIGITS_BASE36[digit]
    }

    /// Returns `Some(ASCII digit)` if the index is within the number's hexadecimal digits,
    ///
    /// For indices beyond the number's hexadecimal digits, returns `None`.
    #[must_use]
    pub const fn digit_at_index16_checked(self, index: u8) -> Option<u8> {
        is![index >= self.count_digits16(), return None];
        let shift = index as u32 * 4;
        let digit = self.0.unbounded_shr(shift) & 0xF;
        Some(TextLut::DIGITS_BASE36[digit])
    }

    /* digit_value_at_ */

    /// Returns the numeric value (0-9) of the decimal digit at the specified index.
    ///
    /// Returns `0` if the index is beyond the number's decimal digits.
    #[must_use]
    pub const fn digit_value_at_index10(self, index: u8) -> u8 {
        is![index >= self.count_digits10(), return 0];
        let power = TextLut::POWERS10[index as usize] as usize;
        (self.0 / power % 10) as u8
    }
    /// Returns `Some(numeric_value)` (0-9) of the decimal digit at the specified index.
    ///
    /// Returns `None` if the index is beyond the number's decimal digits.
    #[must_use]
    pub const fn digit_value_at_index10_checked(self, index: u8) -> Option<u8> {
        is![index >= self.count_digits10(), return None];
        let power = TextLut::POWERS10[index as usize] as usize;
        Some((self.0 / power % 10) as u8)
    }

    /// Returns the numeric value (0-15) of the hexadecimal digit at the specified index.
    ///
    /// Returns `0` if the index is beyond the number's hexadecimal digits.
    #[must_use]
    #[inline(always)]
    pub const fn digit_value_at_index16(self, index: u8) -> u8 {
        let shift = index as u32 * 4;
        (self.0.unbounded_shr(shift) & 0xF) as u8
    }
    /// Returns `Some(numeric_value)` (0-15) if the index is within bounds.
    ///
    /// Returns `None` if the index is beyond the number's hexadecimal digits.
    #[must_use]
    pub const fn digit_value_at_index16_checked(self, index: u8) -> Option<u8> {
        is![index < self.count_digits16(), Some(self.digit_value_at_index16(index)), None]
    }

    //

    #[doc = DOC_DIGIT_AT_POWER_10!()]
    #[must_use]
    #[allow(dead_code)]
    pub(crate) const fn digit_at_power10(self, divisor: usize) -> u8 {
        (self.0 / divisor % 10) as u8 + b'0'
    }
    #[must_use]
    #[cfg(target_pointer_width = "16")]
    pub(crate) const fn digit_at_power16(self, divisor: usize) -> u8 {
        Digits(self.0 as u16).digit_at_power16(divisor as u16)
    }
    #[must_use]
    #[cfg(target_pointer_width = "32")]
    pub(crate) const fn digit_at_power16(self, divisor: usize) -> u8 {
        Digits(self.0 as u32).digit_at_power16(divisor as u32)
    }
    #[doc = DOC_DIGIT_AT_POWER_16!()]
    #[must_use]
    #[allow(dead_code)]
    #[cfg(target_pointer_width = "64")]
    pub(crate) const fn digit_at_power16(self, divisor: usize) -> u8 {
        Digits(self.0 as u64).digit_at_power16(divisor as u64)
    }

    /// Converts a `usize` into a byte array of `5` ascii digits with leading zeros.
    ///
    /// The actual array length depends on the target platform's pointer size.
    ///
    /// You can trim the leading zeros with `Slice::`[`trim_leading()`][crate::Slice::trim_leading].
    #[must_use]
    #[cfg(target_pointer_width = "16")]
    pub const fn digits10(self) -> [u8; Self::MAX_DIGITS_10 as usize] {
        Digits(self.0 as u16).digits10()
    }
    #[must_use]
    #[cfg(target_pointer_width = "16")]
    pub const fn digits16(self) -> [u8; Self::MAX_DIGITS_16 as usize] {
        Digits(self.0 as u16).digits16()
    }

    /// Converts a `usize` into a byte array of `10` ascii digits with leading zeros.
    ///
    /// The actual array length depends on the target platform's pointer size.
    ///
    /// You can trim the leading zeros with `Slice::`[`trim_leading()`][crate::Slice::trim_leading].
    #[must_use]
    #[cfg(target_pointer_width = "32")]
    pub const fn digits10(self) -> [u8; Self::MAX_DIGITS_10 as usize] {
        Digits(self.0 as u32).digits10()
    }
    #[must_use]
    #[cfg(target_pointer_width = "32")]
    pub const fn digits16(self) -> [u8; Self::MAX_DIGITS_16 as usize] {
        Digits(self.0 as u32).digits16()
    }

    /// Converts a `usize` into a byte array of `20` ascii digits with leading zeros.
    ///
    /// The actual array length depends on the target platform's pointer size.
    ///
    /// You can trim the leading zeros with `Slice::`[`trim_leading()`][crate::Slice::trim_leading].
    #[must_use]
    #[cfg(target_pointer_width = "64")]
    pub const fn digits10(self) -> [u8; Self::MAX_DIGITS_10 as usize] {
        Digits(self.0 as u64).digits10()
    }
    /// Converts a `usize` into a byte array of `20` ascii digits with leading zeros.
    ///
    /// The actual array length depends on the target platform's pointer size.
    ///
    /// You can trim the leading zeros with `Slice::`[`trim_leading()`][crate::Slice::trim_leading].
    #[must_use]
    #[cfg(target_pointer_width = "64")]
    pub const fn digits16(self) -> [u8; Self::MAX_DIGITS_16 as usize] {
        Digits(self.0 as u64).digits16()
    }

    #[doc = DOC_WRITE_DIGITS_10!(10)]
    #[must_use]
    #[inline(always)]
    #[cfg(target_pointer_width = "32")]
    pub const fn write_digits10(self, buf: &mut [u8], offset: usize) -> usize {
        Digits(self.0 as u32).write_digits10(buf, offset)
    }
    #[doc = DOC_WRITE_DIGITS_10_FAST!(10)]
    #[must_use]
    #[inline(always)]
    #[cfg(target_pointer_width = "32")]
    pub fn write_digits10_fast(self, buf: &mut [u8], offset: usize) -> usize {
        Digits(self.0 as u32).write_digits10_fast(buf, offset)
    }
    #[doc = DOC_WRITE_DIGITS_10!(20)]
    #[must_use]
    #[inline(always)]
    #[cfg(target_pointer_width = "64")]
    pub const fn write_digits10(self, buf: &mut [u8], offset: usize) -> usize {
        Digits(self.0 as u64).write_digits10(buf, offset)
    }
    #[doc = DOC_WRITE_DIGITS_10_FAST!(20)]
    #[must_use]
    #[inline(always)]
    #[cfg(target_pointer_width = "64")]
    pub fn write_digits10_fast(self, buf: &mut [u8], offset: usize) -> usize {
        Digits(self.0 as u64).write_digits10_fast(buf, offset)
    }

    #[doc = DOC_DIGITS_STR!()] #[rustfmt::skip]
    pub const fn digits10_str(self, width: u8) -> StringU8<{Self::MAX_DIGITS_10 as usize}> {
        let width = Cmp(width).clamp(self.count_digits10(), Self::MAX_DIGITS_10);

        #[cfg(any(feature = "safe_text", not(feature = "unsafe_str")))]
        return crate::unwrap![ok StringU8::<{Self::MAX_DIGITS_10 as usize}>
            ::from_array_nright(self.digits10(), width)];

        #[cfg(all(not(feature = "safe_text"), feature = "unsafe_str"))]
        // SAFETY: the bytes are valid UTF-8
        unsafe { StringU8::<{Self::MAX_DIGITS_10 as usize}>
            ::from_array_nright_unchecked(self.digits10(), width) }
    }
    #[doc = DOC_DIGITS_STR!()] #[rustfmt::skip]
    pub const fn digits16_str(self, width: u8) -> StringU8<{Self::MAX_DIGITS_16 as usize}> {
        let width = Cmp(width).clamp(self.count_digits16(), Self::MAX_DIGITS_16);

        #[cfg(any(feature = "safe_text", not(feature = "unsafe_str")))]
        return crate::unwrap![ok StringU8::<{Self::MAX_DIGITS_16 as usize}>
            ::from_array_nright(self.digits16(), width)];

        #[cfg(all(not(feature = "safe_text"), feature = "unsafe_str"))]
        // SAFETY: the bytes are valid UTF-8
        unsafe { StringU8::<{Self::MAX_DIGITS_16 as usize}>
            ::from_array_nright_unchecked(self.digits16(), width) }
    }
}