Add streaming load/save support for large editor files

examples/ted/InlineProgress.cs

@@ -0,0 +1,20 @@
+namespace Ted;
+
+/// <summary>
+///     Reports progress synchronously for non-hosted app scenarios where <see cref="Progress{T}" />
+///     would queue callbacks to the thread pool instead of an application UI thread.
+/// </summary>
+internal sealed class InlineProgress<T> : IProgress<T>
+{
+    private readonly Action<T> _handler;
+
+    public InlineProgress (Action<T> handler)
+    {
+        _handler = handler ?? throw new ArgumentNullException (nameof (handler));
+    }
+
+    public void Report (T value)
+    {
+        _handler (value);
+    }
+}

examples/ted/Program.cs

@@ -23,13 +23,15 @@
 
 if (!string.IsNullOrWhiteSpace (requestedPath))
 {
+    // Defer onto the app loop so the window renders first, then the file streams in progressively
+    // instead of blocking the UI until the whole file is read.
     if (File.Exists (requestedPath))
     {
-        ted.SetDocument (File.ReadAllText (requestedPath), requestedPath);
+        app.Invoke (() => ted.BeginOpenFile (requestedPath));
     }
     else
     {
-        ted.OpenMissingFile (requestedPath);
+        app.Invoke (() => ted.OpenMissingFile (requestedPath));
     }
 }