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diff --git a/source/lux/host/io.lux b/source/lux/host/io.lux
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+##  Copyright (c) Eduardo Julian. All rights reserved.
+##  This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
+##  If a copy of the MPL was not distributed with this file,
+##  You can obtain one at http://mozilla.org/MPL/2.0/.
+
+(;import lux
+         (lux (data (list #refer #all #open ("" List/Fold)))
+              (codata io)
+              (meta ast
+                    syntax
+                    lux)
+              control/monad)
+         (.. jvm))
+
+## [Functions]
+(do-template [<name> <method> <type> <class>]
+  [(def #export (<name> x)
+     (-> <type> (IO (,)))
+     (@io (_jvm_invokevirtual "java.io.PrintStream" <method> [<class>]
+                              (_jvm_getstatic "java.lang.System" "out") [x])))]
+
+  [write-char "print"   Char "char"]
+  [write      "print"   Text "java.lang.String"]
+  [write-line "println" Text "java.lang.String"]
+  )
+
+(do-template [<name> <type> <op>]
+  [(def #export <name>
+     (IO (Maybe <type>))
+     (let [in (_jvm_getstatic "java.lang.System" "in")
+           reader (_jvm_new "java.io.InputStreamReader" ["java.io.InputStream"] [in])
+           buff-reader (_jvm_new "java.io.BufferedReader" ["java.io.Reader"] [reader])]
+       (@io (let [output (: (Either Text <type>) (try <op>))
+                  _close (: (Either Text (,)) (try (_jvm_invokeinterface "java.io.Closeable" "close" [] buff-reader [])))]
+              (case [output _close]
+                (\or [(#;Left _) _] [_ (#;Left _)]) #;None
+                [(#;Right input) (#;Right _)]       (#;Some input))))))]
+
+  [read-char Char (_jvm_i2c (_jvm_invokevirtual "java.io.BufferedReader" "read" [] buff-reader []))]
+  [read-line Text (_jvm_invokevirtual "java.io.BufferedReader" "readLine" [] buff-reader [])]
+  )
+
+## [Syntax]
+(def simple-bindings^
+  (Parser (List (, Text AST)))
+  (tuple^ (*^ (&^ local-symbol^ id^))))
+
+(defsyntax #export (with-open [bindings simple-bindings^] body)
+  (do Lux/Monad
+    [g!output (gensym "output")
+     #let [code (foldL (: (-> AST (, Text AST) AST)
+                          (lambda [body [res-name res-value]]
+                            (let [g!res-name (symbol$ ["" res-name])]
+                              (` (let [(~ g!res-name) (~ res-value)
+                                       (~ g!output) (~ body)]
+                                   (exec (;_jvm_invokeinterface "java.io.Closeable" "close" [] (~ g!res-name) [])
+                                     (~ g!output)))))))
+                       body
+                       (reverse bindings))]]
+    (wrap (@list code))))