Add Channel.voice_members

This allows you to see which members are currently in a voice
channel.

discord/channel.py

@@ -56,10 +56,15 @@ class Channel(object):
 
         An array of :class:`Roles` that have been overridden from their default
         values in the :attr:`Server.roles` attribute.
+    .. attribute:: voice_members
+
+        An array of :class:`Members` that are currently inside this voice channel.
+        If :attr:`type` is not ``'voice'`` then this is always an empty array.
     """
 
     def __init__(self, **kwargs):
         self.update(**kwargs)
+        self.voice_members = []
 
     def update(self, **kwargs):
         self.name = kwargs.get('name')

discord/server.py

@@ -89,8 +89,17 @@ class Member(User):
         self.is_afk = kwargs.get('suppress', False)
         self.mute = kwargs.get('mute', False)
         self.deaf = kwargs.get('deaf', False)
+        old_channel = getattr(self, 'voice_channel', None)
         self.voice_channel = kwargs.get('voice_channel')
 
+        if old_channel is None and self.voice_channel is not None:
+            # we joined a channel
+            self.voice_channel.voice_members.append(self)
+        elif old_channel is not None and self.voice_channel is None:
+            # we left a channel
+            old_channel.voice_members.remove(self)
+
+
 class Server(object):
     """Represents a Discord server.