openpgp: Add a new way to wrap writers for streaming serialization.

  - Implement `From<'a mut io::Write>` for the writer stack.  While
    this may be neat in some situations, if you have a concrete
    writer `sink`, you need to do some acrobatics to use it, e.g.:

      Signer::new((&mut sink as &mut io::Write).into(), ...)

1 files changed, 7 insertions, 0 deletions

diff --git a/openpgp/src/serialize/stream.rs b/openpgp/src/serialize/stream.rs
index ec605c0a..93809b7b 100644
--- a/openpgp/src/serialize/stream.rs
+++ b/openpgp/src/serialize/stream.rs
@@ -65,6 +65,13 @@ pub fn wrap<'a, W: 'a + io::Write>(w: W) -> writer::Stack<'a, Cookie> {
 }
 
 
+impl<'a> From<&'a mut io::Write> for writer::Stack<'a, Cookie> {
+    fn from(w: &'a mut io::Write) -> Self {
+        writer::Generic::new(w, Cookie::new(0))
+    }
+}
+
+
 /// Writes an arbitrary packet.
 ///
 /// This writer can be used to construct arbitrary OpenPGP packets.