Function encode_integer_into 

pub fn encode_integer_into<W: Write>(
    value: usize,
    prefix_size: u8,
    leading_bits: u8,
    writer: &mut W,
) -> Result<()>

Encode an integer to the representation defined by HPACK, writing it into the provider io::Write instance. Also allows the caller to specify the leading bits of the first octet. Any bits that are already set within the last prefix_size bits will be cleared and overwritten by the integer’s representation (in other words, only the first 8 - prefix_size bits from the leading_bits octet are reflected in the first octet emitted by the function.

Example

use loona_hpack::encoder::encode_integer_into;

{
    // No bits specified in the 3 most significant bits of the first octet
    let mut vec = Vec::new();
    encode_integer_into(10, 5, 0, &mut vec);
    assert_eq!(vec, vec![10]);
}
{
    // The most significant bit should be set; i.e. the 3 most significant
    // bits are 100.
    let mut vec = Vec::new();
    encode_integer_into(10, 5, 0x80, &mut vec);
    assert_eq!(vec, vec![0x8A]);
}
{
    // The most leading bits number has a bit set within the last prefix-size
    // bits -- they are ignored by the function
    // bits are 100.
    let mut vec = Vec::new();
    encode_integer_into(10, 5, 0x10, &mut vec);
    assert_eq!(vec, vec![0x0A]);
}
{
    let mut vec = Vec::new();
    encode_integer_into(1337, 5, 0, &mut vec);
    assert_eq!(vec, vec![31, 154, 10]);
}