/// Trait to interact with immediate operands.
pub(crate) trait Imm {
    /// Get immediate operand as slice of bytes.
    fn bytes(&self) -> &[u8];
}

macro_rules! impl_imm {
    ($name:ident, $size:expr, from: $( $from:ty ),* $(,)?) => {
        /// Immediate operand.
        pub struct $name([u8; $size]);

        impl Imm for $name {
            /// Get immediate operand as slice of bytes.
            fn bytes(&self) -> &[u8] {
                &self.0
            }
        }

        $(
        impl From<$from> for $name {
            fn from(imm: $from) -> Self {
                let mut buf = [0u8; $size];
                let imm = imm.to_ne_bytes();
                buf[0..imm.len()].copy_from_slice(&imm);
                $name(buf)
            }
        }
        )*
    }
}

impl_imm!(Imm8, 1, from: u8, i8);
impl_imm!(Imm16, 2, from: u16, i16, u8, i8);
impl_imm!(Imm32, 4, from: u32, i32, u16, i16, u8, i8);
impl_imm!(Imm64, 8, from: u64, i64, u32, i32, u16, i16, u8, i8);