Clean up temp file on exit, updated readme

Readme.md

@@ -13,8 +13,10 @@ npm install repl-edit
 Usage
 =====
 
-You can fire up a repl with editing capabilities by running `node-repl-edit`
-or extend an existing repl session by typing `require('repl-edit').extend(global)`.
+You can fire up a repl with editing capabilities by running `node-repl-edit`.
+
+(It would be nice to extend an existing repl session but that's not possible with
+Node's repl module right now.)
 
 
 Commands
@@ -63,6 +65,9 @@ capability to provide commands like `.edit` and `.stash <filename>`.
 The first time edit() is run in a repl instead of an empty file the command should be seeded
 with the last command that was executed.
 
+If the native repl module exports the currently running repl object it will be possible to attach
+to an existing repl instead of having to run a separate binary that loads a repl.
+
 
 License
 =======

lib/index.js

@@ -5,17 +5,19 @@
 // github.com/samsonjs/repl-edit
 //
 
-// TODO proper error handling
+// TODO proper error handling, better intregration with node/lib/repl.js
 
 var fs = require('fs')
+  , repl = require('repl')
   , _repl
 
 exports.startRepl = function() {
     console.log('Commands: edit(), run(), stash(filename), unstash(filename), setEditor(editor)')
     // TODO extend the repl context instead, problem is that repl.js:resetContext() isn't exported
     //      so simple assignments to _repl.context can't survive .clear yet
     exports.extend(global)
-    _repl = require('repl').start()
+    _repl = repl.start()
+    return exports
 }
 
 exports.extend = function(obj) {
@@ -91,6 +93,16 @@ exports.extend = function(obj) {
             sys.pump(read, fs.createWriteStream(_tmpfile))
         })
     }
+
+    process.on('exit', function() {
+        try {
+            fs.unlinkSync(_tmpfile)
+        } catch (e) {
+            // might not exist
+        }
+    })
+
+    return exports
 }
 
 function pausingRepl(fn) {
@@ -105,7 +117,7 @@ function pausingRepl(fn) {
         _repl.displayPrompt()
     })
 }
-    
+
 function runFile(filename, callback) {
     var Script = process.binding('evals').Script
       , evalcx = Script.runInContext