moc 0.19.2

Library made to create and manipulate HEALPix Multi-Order Coverages maps (MOCs), see https://ivoa.net/documents/MOC/
Documentation 
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use std::io::{BufRead, BufReader, Read, Seek};

use flate2::read::GzDecoder;

const GZ_MAGIC_NUM: [u8; 2] = [0x1F, 0x8B];
const GZ_MAGIC_NUM_LEN: usize = GZ_MAGIC_NUM.len();

pub fn is_gz<R: Read + Seek>(reader: &mut BufReader<R>) -> Result<bool, std::io::Error> {
  let mut gz_magic_bytes = [0u8; 2];
  reader.read_exact(&mut gz_magic_bytes)?;
  reader.seek_relative(-(GZ_MAGIC_NUM_LEN as i64))?;
  Ok(gz_magic_bytes == GZ_MAGIC_NUM)
}

/// Returns an object implementing `BufRead` and decompressing on-th-fly the input `BufRead`.
pub fn uncompress<R: BufRead>(reader: R) -> BufReader<GzDecoder<R>> {
  BufReader::new(GzDecoder::new(reader))
}

/*pub fn uncompress_if_needed<R, O, F>(
  mut reader: BufReader<R>,
  op: F
) -> Result<O, std::io::Error>
  where
    R: Read + Seek,
    O: ,
    F: Fn(Box<dyn BufRead>) -> Result<O, std::io::Error>
{
  if is_gz(&mut reader)? {
    op(Box::new(uncompress(reader)))
  } else {
    op(Box::new(reader))
  }
}*/