5 files changed, 45 insertions, 23 deletions
diff --git a/stdlib/source/lux/world/console.lux b/stdlib/source/lux/world/console.lux
index 99d290479..209063dfd 100644
--- a/stdlib/source/lux/world/console.lux
+++ b/stdlib/source/lux/world/console.lux
@@ -4,7 +4,8 @@
     [monad (#+ do)]
     ["ex" exception (#+ exception:)]
     [security
-     ["." taint (#+ Dirty taint)]]]
+     ["." taint (#+ Dirty taint)]
+     [capability (#+ Capability)]]]
    [data
     ["." error (#+ Error)]
     ["." text
@@ -25,14 +26,23 @@
   [cannot-close]
   )
 
+(type: #export (Can-Read ! o)
+  (Capability [] (! (Error (Dirty o)))))
+
+(type: #export (Can-Write ! i)
+  (Capability i (! (Error Any))))
+
+(type: #export (Can-Close !)
+  (Capability [] (! (Error Any))))
+
 (signature: #export (Console !)
-  (: (-> Any (! (Error (Dirty Nat))))
+  (: (Can-Read ! Nat)
      read)
-  (: (-> Any (! (Error (Dirty Text))))
+  (: (Can-Read ! Text)
      read-line)
-  (: (-> Text (! (Error Any)))
+  (: (Can-Write ! Text)
      write)
-  (: (-> Any (! (Error Any)))
+  (: (Can-Close !)
      close))
 
 (def: #export (async console)
diff --git a/stdlib/source/lux/world/net.lux b/stdlib/source/lux/world/net.lux
index 867430af0..a29df5f84 100644
--- a/stdlib/source/lux/world/net.lux
+++ b/stdlib/source/lux/world/net.lux
@@ -1,5 +1,10 @@
 (.module:
-  lux)
+  [lux #*
+   [data
+    [error (#+ Error)]]
+   [control
+    [security
+     [capability (#+ Capability)]]]])
 
 (type: #export Address Text)
 
@@ -8,3 +13,12 @@
 (type: #export Location
   {#address Address
    #port Port})
+
+(type: #export (Can-Read ! o)
+  (Capability Nat (! (Error o))))
+
+(type: #export (Can-Write ! i)
+  (Capability i (! (Error Any))))
+
+(type: #export (Can-Close !)
+  (Capability [] (! (Error Any))))
diff --git a/stdlib/source/lux/world/net/tcp.jvm.lux b/stdlib/source/lux/world/net/tcp.jvm.lux
index 329d256e0..add7427cb 100644
--- a/stdlib/source/lux/world/net/tcp.jvm.lux
+++ b/stdlib/source/lux/world/net/tcp.jvm.lux
@@ -17,7 +17,7 @@
    [platform
     [compiler
      ["." host]]]]
-  ["." //])
+  ["." // (#+ Can-Read Can-Write Can-Close)])
 
 (import: java/lang/AutoCloseable
   (close [] #io #try void))
@@ -45,13 +45,13 @@
 ############################################################
 
 (signature: #export (TCP !)
-  (: (-> Nat (! (Error [Nat (Dirty Binary)])))
+  (: (Can-Read ! [Nat (Dirty Binary)])
      read)
 
-  (: (-> Binary (! (Error Any)))
+  (: (Can-Write ! Binary)
      write)
 
-  (: (-> Any (! (Error Any)))
+  (: (Can-Close !)
      close))
 
 (def: #export (async tcp)
diff --git a/stdlib/source/lux/world/net/udp.jvm.lux b/stdlib/source/lux/world/net/udp.jvm.lux
index 842f1c969..f27ca1c5e 100644
--- a/stdlib/source/lux/world/net/udp.jvm.lux
+++ b/stdlib/source/lux/world/net/udp.jvm.lux
@@ -20,7 +20,7 @@
    [platform
     [compiler
      ["." host]]]]
-  ["." // (#+ Location)])
+  ["." // (#+ Location Can-Read Can-Write Can-Close)])
 
 (import: java/lang/AutoCloseable
   (close [] #io #try void))
@@ -56,23 +56,21 @@
   (ex.report ["Address" address]))
 
 (signature: #export (UDP !)
-  (: (-> Nat (! (Error [Nat Location (Dirty Binary)])))
+  (: (Can-Read ! [Nat Location (Dirty Binary)])
      read)
 
-  (: (-> Location Binary (! (Error Any)))
+  (: (Can-Write ! [Location Binary])
      write)
 
-  (: (-> Any (! (Error Any)))
+  (: (Can-Close !)
      close))
 
 (def: #export (async udp)
   (-> (UDP IO) (UDP Promise))
-  (`` (structure (def: read (|>> (:: udp read) promise.future))
-                 
-                 (def: (write location data)
-                   (promise.future (:: udp write location data)))
-                 
-                 (def: close (|>> (:: udp close) promise.future)))))
+  (`` (structure (~~ (do-template [<name>]
+                       [(def: <name> (|>> (:: udp <name>) promise.future))]
+
+                       [read] [write] [close])))))
 
 (`` (for {(~~ (static host.jvm))
           (as-is (def: (resolve address)
@@ -98,7 +96,7 @@
                                             #//.port (.nat (DatagramPacket::getPort packet))}
                                            (taint data)]))))
 
-                              (def: (write location data)
+                              (def: (write [location data])
                                 (do io.Monad<Process>
                                   [address (resolve (get@ #//.address location))]
                                   (DatagramSocket::send (DatagramPacket::new|send data +0 (.int (binary.size data)) address (.int (get@ #//.port location)))
diff --git a/stdlib/test/test/lux/world/net/udp.lux b/stdlib/test/test/lux/world/net/udp.lux
index d630816d8..e41082d35 100644
--- a/stdlib/test/test/lux/world/net/udp.lux
+++ b/stdlib/test/test/lux/world/net/udp.lux
@@ -42,12 +42,12 @@
                            [server (@.server port)
                             client @.client
                             ####################
-                            _ (:: client write [localhost port] from)
+                            _ (:: client write [[localhost port] from])
                             [bytes-from [from-address from-port] temp] (:: server read size)
                             #let [from-worked? (and (n/= size bytes-from)
                                                     (:: binary.Equivalence<Binary> = from (taint.trust temp)))]
                             ####################
-                            _ (:: server write [from-address from-port] to)
+                            _ (:: server write [[from-address from-port] to])
                             [bytes-to [to-address to-port] temp] (:: client read size)
                             #let [to-worked? (and (n/= size bytes-to)
                                                   (:: binary.Equivalence<Binary> = to (taint.trust temp))