openpgp: Use marker types to denote a Key's type.

  - In addition to providing some added protection, this allows us to
    implement 'From<Key<_, _>> for Packet'.

2 files changed, 32 insertions, 16 deletions

diff --git a/guide/src/chapter_01.md b/guide/src/chapter_01.md
index 8d973e07..d82d8bb0 100644
--- a/guide/src/chapter_01.md
+++ b/guide/src/chapter_01.md
@@ -14,6 +14,7 @@ use std::io::{self, Write};
 extern crate failure;
 extern crate sequoia_openpgp as openpgp;
 use openpgp::serialize::stream::*;
+use openpgp::packet::prelude::*;
 use openpgp::parse::stream::*;
 
 const MESSAGE: &'static str = "дружба";
@@ -49,8 +50,9 @@ fn main() {
 # fn sign(sink: &mut Write, plaintext: &str, tsk: &openpgp::TPK)
 #            -> openpgp::Result<()> {
 #     // Get the keypair to do the signing from the TPK.
-#     let mut keypair = tsk.keys_valid().signing_capable().nth(0).unwrap().2
-#         .clone().into_keypair()?;
+#     let key : key::UnspecifiedSecret
+#         = tsk.keys_valid().signing_capable().nth(0).unwrap().2.clone().into();
+#     let mut keypair = key.into_keypair()?;
 #
 #     // Start streaming an OpenPGP message.
 #     let message = Message::new(sink);
@@ -156,6 +158,7 @@ create it:
 # extern crate sequoia_openpgp as openpgp;
 # use openpgp::serialize::stream::*;
 # use openpgp::parse::stream::*;
+# use openpgp::packet::prelude::*;
 #
 # const MESSAGE: &'static str = "дружба";
 #
@@ -190,8 +193,9 @@ fn generate() -> openpgp::Result<openpgp::TPK> {
 # fn sign(sink: &mut Write, plaintext: &str, tsk: &openpgp::TPK)
 #            -> openpgp::Result<()> {
 #     // Get the keypair to do the signing from the TPK.
-#     let mut keypair = tsk.keys_valid().signing_capable().nth(0).unwrap().2
-#         .clone().into_keypair()?;
+#     let key : key::UnspecifiedSecret
+#         = tsk.keys_valid().signing_capable().nth(0).unwrap().2.clone().into();
+#     let mut keypair = key.into_keypair()?;
 #
 #     // Start streaming an OpenPGP message.
 #     let message = Message::new(sink);
@@ -296,6 +300,7 @@ implements [`io::Write`], and we simply write the plaintext to it.
 # extern crate failure;
 # extern crate sequoia_openpgp as openpgp;
 # use openpgp::serialize::stream::*;
+# use openpgp::packet::prelude::*;
 # use openpgp::parse::stream::*;
 #
 # const MESSAGE: &'static str = "дружба";
@@ -331,8 +336,9 @@ implements [`io::Write`], and we simply write the plaintext to it.
 fn sign(sink: &mut Write, plaintext: &str, tsk: &openpgp::TPK)
            -> openpgp::Result<()> {
     // Get the keypair to do the signing from the TPK.
-    let mut keypair = tsk.keys_valid().signing_capable().nth(0).unwrap().2
-        .clone().into_keypair()?;
+    let key : key::UnspecifiedSecret
+        = tsk.keys_valid().signing_capable().nth(0).unwrap().2.clone().into();
+    let mut keypair = key.into_keypair()?;
 
     // Start streaming an OpenPGP message.
     let message = Message::new(sink);
@@ -448,6 +454,7 @@ Verified data can be read from this using [`io::Read`].
 # extern crate failure;
 # extern crate sequoia_openpgp as openpgp;
 # use openpgp::serialize::stream::*;
+# use openpgp::packet::prelude::*;
 # use openpgp::parse::stream::*;
 # 
 # const MESSAGE: &'static str = "дружба";
@@ -483,8 +490,9 @@ Verified data can be read from this using [`io::Read`].
 # fn sign(sink: &mut Write, plaintext: &str, tsk: &openpgp::TPK)
 #            -> openpgp::Result<()> {
 #     // Get the keypair to do the signing from the TPK.
-#     let mut keypair = tsk.keys_valid().signing_capable().nth(0).unwrap().2
-#         .clone().into_keypair()?;
+#     let key : key::UnspecifiedSecret
+#         = tsk.keys_valid().signing_capable().nth(0).unwrap().2.clone().into();
+#     let mut keypair = key.into_keypair()?;
 # 
 #     // Start streaming an OpenPGP message.
 #     let message = Message::new(sink);
diff --git a/guide/src/chapter_02.md b/guide/src/chapter_02.md
index b6463033..7c564ff0 100644
--- a/guide/src/chapter_02.md
+++ b/guide/src/chapter_02.md
@@ -15,6 +15,7 @@ extern crate sequoia_openpgp as openpgp;
 use openpgp::crypto::SessionKey;
 use openpgp::constants::SymmetricAlgorithm;
 use openpgp::serialize::stream::*;
+use openpgp::packet::prelude::*;
 use openpgp::parse::stream::*;
 
 const MESSAGE: &'static str = "дружба";
@@ -118,9 +119,10 @@ fn main() {
 #         where D: FnMut(SymmetricAlgorithm, &SessionKey) -> openpgp::Result<()>
 #     {
 #         // The encryption key is the first and only subkey.
-#         let key = self.secret.subkeys().nth(0)
+#         let key : key::UnspecifiedSecret
+#             = self.secret.subkeys().nth(0)
 #             .map(|binding| binding.key().clone())
-#             .unwrap();
+#             .unwrap().into();
 #
 #         // The secret key is not encrypted.
 #         let mut pair = key.into_keypair().unwrap();
@@ -149,6 +151,7 @@ create it:
 # use openpgp::crypto::SessionKey;
 # use openpgp::constants::SymmetricAlgorithm;
 # use openpgp::serialize::stream::*;
+# use openpgp::packet::prelude::*;
 # use openpgp::parse::stream::*;
 #
 # const MESSAGE: &'static str = "дружба";
@@ -252,9 +255,10 @@ fn generate() -> openpgp::Result<openpgp::TPK> {
 #         where D: FnMut(SymmetricAlgorithm, &SessionKey) -> openpgp::Result<()>
 #     {
 #         // The encryption key is the first and only subkey.
-#         let key = self.secret.subkeys().nth(0)
+#         let key : key::UnspecifiedSecret
+#             = self.secret.subkeys().nth(0)
 #             .map(|binding| binding.key().clone())
-#             .unwrap();
+#             .unwrap().into();
 #
 #         // The secret key is not encrypted.
 #         let mut pair = key.into_keypair().unwrap();
@@ -283,6 +287,7 @@ implements [`io::Write`], and we simply write the plaintext to it.
 # use openpgp::crypto::SessionKey;
 # use openpgp::constants::SymmetricAlgorithm;
 # use openpgp::serialize::stream::*;
+# use openpgp::packet::prelude::*;
 # use openpgp::parse::stream::*;
 #
 # const MESSAGE: &'static str = "дружба";
@@ -386,9 +391,10 @@ fn encrypt(sink: &mut Write, plaintext: &str, recipient: &openpgp::TPK)
 #         where D: FnMut(SymmetricAlgorithm, &SessionKey) -> openpgp::Result<()>
 #     {
 #         // The encryption key is the first and only subkey.
-#         let key = self.secret.subkeys().nth(0)
+#         let key : key::UnspecifiedSecret
+#             = self.secret.subkeys().nth(0)
 #             .map(|binding| binding.key().clone())
-#             .unwrap();
+#             .unwrap().into();
 #
 #         // The secret key is not encrypted.
 #         let mut pair = key.into_keypair().unwrap();
@@ -431,6 +437,7 @@ Decrypted data can be read from this using [`io::Read`].
 # use openpgp::crypto::SessionKey;
 # use openpgp::constants::SymmetricAlgorithm;
 # use openpgp::serialize::stream::*;
+# use openpgp::packet::prelude::*;
 # use openpgp::parse::stream::*;
 #
 # const MESSAGE: &'static str = "дружба";
@@ -534,9 +541,10 @@ impl<'a> DecryptionHelper for Helper<'a> {
         where D: FnMut(SymmetricAlgorithm, &SessionKey) -> openpgp::Result<()>
     {
         // The encryption key is the first and only subkey.
-        let key = self.secret.subkeys().nth(0)
+        let key : key::UnspecifiedSecret
+            = self.secret.subkeys().nth(0)
             .map(|binding| binding.key().clone())
-            .unwrap();
+            .unwrap().into();
 
         // The secret key is not encrypted.
         let mut pair = key.into_keypair().unwrap();