no chaining for private functions, added example

Author: lathoub

examples/Chaining/Chaining.ino

@@ -0,0 +1,37 @@
+#include <MIDI.h>
+
+MIDI_CREATE_DEFAULT_INSTANCE();
+
+void setup()
+{
+    pinMode(2, INPUT);
+    
+    MIDI // chaining MIDI commands - order is from top to bottom (turnThruOff,... begin)
+        .turnThruOff()
+        // using a lamdba function for this callbacks
+        .setHandleNoteOn([](byte channel, byte note, byte velocity)
+            {
+                // Do whatever you want when a note is pressed.
+
+                // Try to keep your callbacks short (no delays ect)
+                // otherwise it would slow down the loop() and have a bad impact
+                // on real-time performance.
+            })
+        .setHandleNoteOff([](byte channel, byte note, byte velocity)
+            {
+                // Do something when the note is released.
+                // Note that NoteOn messages with 0 velocity are interpreted as NoteOffs.
+            })
+        .begin(MIDI_CHANNEL_OMNI); // Initiate MIDI communications, listen to all channels
+}
+
+void loop()
+{
+    // Call MIDI.read the fastest you can for real-time performance.
+    MIDI.read();
+
+    if (digitalRead(2))
+        MIDI // chained sendNoteOn commands
+            .sendNoteOn(42, 127, 1)
+            .sendNoteOn(40, 54, 1);
+}

src/MIDI.h

@@ -208,7 +208,7 @@ class MidiInterface
     inline MidiInterface& disconnectCallbackFromType(MidiType inType);
 
 private:
-    MidiInterface& launchCallback();
+    void launchCallback();
 
     void (*mMessageCallback)(const MidiMessage& message) = nullptr;
     ErrorCallback mErrorCallback = nullptr;
@@ -244,7 +244,7 @@ class MidiInterface
     inline MidiInterface& setThruFilterMode(Thru::Mode inThruFilterMode);
 
 private:
-    MidiInterface& thruFilter(byte inChannel);
+    void thruFilter(byte inChannel);
 
     // -------------------------------------------------------------------------
     // MIDI Parsing

src/MIDI.hpp

@@ -1341,7 +1341,7 @@ MidiInterface<Transport, Settings, Platform>& MidiInterface<Transport, Settings,
 
 // Private - launch callback function based on received type.
 template<class Transport, class Settings, class Platform>
-MidiInterface<Transport, Settings, Platform>& MidiInterface<Transport, Settings, Platform>::launchCallback()
+void MidiInterface<Transport, Settings, Platform>::launchCallback()
 {
     if (mMessageCallback != 0) mMessageCallback(mMessage);
 
@@ -1449,11 +1449,11 @@ inline MidiInterface<Transport, Settings, Platform>& MidiInterface<Transport, Se
 // - Channel messages are passed to the output whether their channel
 //   is matching the input channel and the filter setting
 template<class Transport, class Settings, class Platform>
-MidiInterface<Transport, Settings, Platform>& MidiInterface<Transport, Settings, Platform>::thruFilter(Channel inChannel)
+void MidiInterface<Transport, Settings, Platform>::thruFilter(Channel inChannel)
 {
     // If the feature is disabled, don't do anything.
     if (!mThruActivated || (mThruFilterMode == Thru::Off))
-        return *this;
+        return;
 
     // First, check if the received message is Channel
     if (mMessage.type >= NoteOff && mMessage.type <= PitchBend)
@@ -1532,8 +1532,6 @@ MidiInterface<Transport, Settings, Platform>& MidiInterface<Transport, Settings,
                 break; // LCOV_EXCL_LINE - Unreacheable code, but prevents unhandled case warning.
         }
     }
-
-    return *this;
 }
 
 END_MIDI_NAMESPACE