wiwi/parser/
input.rs

1use crate::prelude::*;
2
3pub trait Input: Sized {
4	type ConstSize<const N: usize>: Sized;
5	type ConstSizeOwned<const N: usize>: Sized + 'static;
6
7	fn len(&self) -> usize;
8
9	#[inline]
10	fn is_empty(&self) -> bool {
11		self.len() == 0
12	}
13
14	#[inline]
15	fn starts_with<N>(&self, needle: &N) -> bool
16	where
17		N: Needle<Self>
18	{
19		needle.input_starts_with(self)
20	}
21
22	fn take_first(&self, i: usize) -> Option<(Self, Self)>;
23	fn take_first_const<const N: usize>(&self) -> Option<(Self::ConstSize<N>, Self)>;
24	fn take_first_const_owned<const N: usize>(&self) -> Option<(Self::ConstSizeOwned<N>, Self)>;
25}
26
27pub trait Needle<I>
28where
29	I: Input
30{
31	fn len(&self) -> usize;
32
33	#[inline]
34	fn is_empty(&self) -> bool {
35		self.len() == 0
36	}
37
38	fn input_starts_with(&self, input: &I) -> bool;
39}
40
41impl<'h> Input for &'h [u8] {
42	type ConstSize<const N: usize> = &'h [u8; N];
43	type ConstSizeOwned<const N: usize> = [u8; N];
44
45	#[inline]
46	fn len(&self) -> usize {
47		(**self).len()
48	}
49
50	#[inline]
51	fn take_first(&self, i: usize) -> Option<(&'h [u8], &'h [u8])> {
52		self.split_at_checked(i)
53	}
54
55	#[inline]
56	fn take_first_const<const N: usize>(&self) -> Option<(Self::ConstSize<N>, Self)> {
57		self.split_at_checked(N).map(|(output, remaining_input)| (
58			// SAFETY: ptr derived from `output`, which is a slice of len `N`
59			unsafe { &*output.as_ptr().cast() },
60			remaining_input
61		))
62	}
63
64	#[inline]
65	fn take_first_const_owned<const N: usize>(&self) -> Option<(Self::ConstSizeOwned<N>, Self)> {
66		self.take_first_const().map(|(output, remaining_input)| (*output, remaining_input))
67	}
68}
69
70impl<'h> Needle<&'h [u8]> for &[u8] {
71	#[inline]
72	fn len(&self) -> usize {
73		(**self).len()
74	}
75
76	#[inline]
77	fn input_starts_with(&self, input: &&'h [u8]) -> bool {
78		input.starts_with(self)
79	}
80}
wiwi/parser/input.rs

wiwi/parser/
input.rs
