musli_binary_common/
writer.rs

1//! Trait for governing how a particular sink of bytes is written to.
2//!
3//! To adapt [std::io::Write] types, see the [wrap][crate::io::wrap] function.
4
5use core::fmt;
6
7use musli::error::Error;
8
9/// The trait governing how a writer works.
10pub trait Writer {
11    /// The error type raised by the writer.
12    type Error: Error;
13
14    /// Write bytes to the current writer.
15    fn write_bytes(&mut self, bytes: &[u8]) -> Result<(), Self::Error>;
16
17    /// Write a single byte.
18    #[inline]
19    fn write_byte(&mut self, b: u8) -> Result<(), Self::Error> {
20        self.write_bytes(&[b])
21    }
22
23    /// Write an array to the current writer.
24    #[inline]
25    fn write_array<const N: usize>(&mut self, array: [u8; N]) -> Result<(), Self::Error> {
26        self.write_bytes(&array)
27    }
28}
29
30impl<W> Writer for &mut W
31where
32    W: ?Sized + Writer,
33{
34    type Error = W::Error;
35
36    #[inline]
37    fn write_bytes(&mut self, bytes: &[u8]) -> Result<(), Self::Error> {
38        (*self).write_bytes(bytes)
39    }
40
41    #[inline]
42    fn write_byte(&mut self, b: u8) -> Result<(), Self::Error> {
43        (*self).write_byte(b)
44    }
45
46    #[inline]
47    fn write_array<const N: usize>(&mut self, array: [u8; N]) -> Result<(), Self::Error> {
48        (*self).write_array(array)
49    }
50}
51
52decl_message_repr!(VecWriterErrorRepr, "failed to write to vector");
53
54/// An error raised while decoding a slice.
55#[derive(Debug)]
56pub struct VecWriterError(VecWriterErrorRepr);
57
58impl fmt::Display for VecWriterError {
59    #[inline]
60    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
61        self.0.fmt(f)
62    }
63}
64
65impl Error for VecWriterError {
66    #[inline]
67    fn custom<T>(message: T) -> Self
68    where
69        T: 'static + Send + Sync + fmt::Display + fmt::Debug,
70    {
71        Self(VecWriterErrorRepr::collect(message))
72    }
73
74    #[inline]
75    fn message<T>(message: T) -> Self
76    where
77        T: fmt::Display,
78    {
79        Self(VecWriterErrorRepr::collect(message))
80    }
81}
82
83#[cfg(feature = "std")]
84impl std::error::Error for VecWriterError {}
85
86#[cfg(feature = "std")]
87impl Writer for Vec<u8> {
88    type Error = VecWriterError;
89
90    #[inline]
91    fn write_bytes(&mut self, bytes: &[u8]) -> Result<(), Self::Error> {
92        self.extend_from_slice(bytes);
93        Ok(())
94    }
95
96    #[inline]
97    fn write_byte(&mut self, b: u8) -> Result<(), Self::Error> {
98        self.push(b);
99        Ok(())
100    }
101
102    #[inline]
103    fn write_array<const N: usize>(&mut self, array: [u8; N]) -> Result<(), Self::Error> {
104        self.extend_from_slice(&array[..]);
105        Ok(())
106    }
107}
musli_binary_common/writer.rs

musli_binary_common/
writer.rs
