parst 0.2.0

declarative parsing
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

use std::{array::try_from_fn, marker::PhantomData, ops::Deref};

use crate::{Deparsable, PResult, PResultBytes, Parsable};

impl<'a, T, Ctx, const N: usize> Parsable<'a, [u8], Ctx> for [T; N]
where
	Ctx: Copy,
	T: Parsable<'a, [u8], Ctx>,
{
	fn read(mut source: &'a [u8], context: Ctx) -> PResultBytes<Self> {
		try_from_fn(|_| {
			let (element, this_bytes) = Parsable::read(source, context)?;
			source = this_bytes;
			Ok(element)
		})
		.map(|array| (array, source))
	}
}

impl<T, const N: usize> Deparsable for [T; N]
where
	T: Deparsable,
{
	fn write(&self, w: &mut impl std::io::Write) -> std::io::Result<()> {
		self.iter().try_for_each(|element| element.write(&mut *w))
	}
}

macro_rules! impl_tuple {
	($name:ident $ty:ident) => {
        impl_tuple!(@impl $name $ty);
    };
    ($name:ident $ty:ident $( $N:ident $T:ident )+) => {
        impl_tuple!($( $N $T )+);
        impl_tuple!(@impl $name $ty $( $N $T )+);
    };
	(@impl $( $N:ident $T:ident )+) => {
		impl<'a, S, Ctx, $( $T ),+> Parsable<'a, S, Ctx> for ($( $T, )+)
		where
            Ctx: Copy,
            $(
                $T: Parsable<'a, S, Ctx>,
            )+
		{
			fn read(source: &'a S, context: Ctx) -> PResult<Self, S> {
                $(
                    let ($N, source) = Parsable::read(source, context)?;
                )+
                Ok((($( $N, )+), source))
			}
		}

		impl<$( $T ),+> Deparsable for ($( $T, )+)
		where
			$(
				$T: Deparsable,
			)+
		{
			fn write(&self, w: &mut impl std::io::Write) -> std::io::Result<()> {
				let ( $( $N, )+ ) = self;
				$(
					$N.write(&mut *w)?;
				)+
				Ok(())
			}
		}
	};
}

impl_tuple!(a A b B c C d D e E f F g G h H);

impl<'a, Src, Ctx, T> Parsable<'a, Src, Ctx> for Vec<T>
where
	Src: ?Sized,
	Ctx: Copy,
	T: Parsable<'a, Src, Ctx>,
{
	fn read(mut source: &'a Src, context: Ctx) -> PResult<Self, Src> {
		let mut v = Vec::new();
		while let Ok((element, remainder)) = Parsable::read(source, context) {
			v.push(element);
			source = remainder;
		}
		Ok((v, source))
	}
}

impl<T> Deparsable for Vec<T>
where
	T: Deparsable,
{
	fn write(&self, w: &mut impl std::io::Write) -> std::io::Result<()> {
		for element in self {
			element.write(&mut *w)?;
		}
		Ok(())
	}
}

impl<'a, Src, Ctx, T> Parsable<'a, Src, Ctx> for Box<T>
where
	Src: ?Sized,
	T: Parsable<'a, Src, Ctx>,
{
	fn read(source: &'a Src, context: Ctx) -> PResult<Self, Src> {
		let (boxed, source) = Parsable::read(source, context)?;
		Ok((Box::new(boxed), source))
	}
}

impl<T> Deparsable for Box<T>
where
	T: Deparsable,
{
	fn write(&self, w: &mut impl std::io::Write) -> std::io::Result<()> {
		self.deref().write(&mut *w)
	}
}

impl<'a, Src, Ctx, T> Parsable<'a, Src, Ctx> for Option<T>
where
	Src: ?Sized,
	T: Parsable<'a, Src, Ctx>,
{
	fn read(source: &'a Src, context: Ctx) -> PResult<Self, Src> {
		match Parsable::read(source, context) {
			Ok((inner, source)) => Ok((Some(inner), source)),
			Err(_) => Ok((None, source)),
		}
	}
}

impl<T> Deparsable for Option<T>
where
	T: Deparsable,
{
	fn write(&self, w: &mut impl std::io::Write) -> std::io::Result<()> {
		match self {
			Some(inner) => inner.write(&mut *w),
			None => Ok(()),
		}
	}
}

impl<Src, Ctx, T> Parsable<'_, Src, Ctx> for PhantomData<T>
where
	Src: ?Sized,
{
	fn read(source: &Src, _context: Ctx) -> PResult<Self, Src> { Ok((PhantomData, source)) }
}