rw-types 0.1.0

Library for reading and writing types.
Documentation 
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use std::io;

use crate::{Endian, read::ReadExt};

/// A trait for objects that can be read.
pub trait Readable: Sized {
    /// Reads this object with the specified writer and endian.
    fn read(reader: impl ReadExt, endian: Endian) -> io::Result<Self>;
}

macro_rules! int {
    (impl $ty:ty) => {
        impl Readable for $ty {
            fn read(mut reader: impl ReadExt, endian: Endian) -> io::Result<Self> {
                let mut bytes = [0; std::mem::size_of::<Self>()];
                reader.read_exact(&mut bytes)?;
                let value = match endian {
                    Endian::Big => Self::from_be_bytes(bytes),
                    Endian::Little => Self::from_le_bytes(bytes),
                    Endian::Native => Self::from_ne_bytes(bytes),
                };
                Ok(value)
            }
        }
    };
    ($($ty:ty)+) => {
        $( int!(impl $ty); )+
    };
}

int!(u8 u16 u32 u64 u128);
int!(i8 i16 i32 i64 i128);
int!(f32 f64);

impl Readable for bool {
    fn read(mut reader: impl ReadExt, endian: Endian) -> io::Result<Self> {
        let raw = reader.read_type::<u8>(endian)?;
        if raw != 0 && raw != 1 {
            return Err(io::Error::from(io::ErrorKind::InvalidData));
        }
        let value = raw == 1;
        Ok(value)
    }
}