better prefix

discord/ext/commands/context.py

@@ -26,6 +26,7 @@ DEALINGS IN THE SOFTWARE.
 
 import discord.abc
 import discord.utils
+import re
 
 class Context(discord.abc.Messageable):
     r"""Represents the context in which a command is being invoked under.
@@ -50,8 +51,6 @@ class Context(discord.abc.Messageable):
         A dictionary of transformed arguments that were passed into the command.
         Similar to :attr:`args`\, if this is accessed in the
         :func:`on_command_error` event then this dict could be incomplete.
-    prefix: :class:`str`
-        The prefix that was used to invoke the command.
     command: :class:`Command`
         The command that is being invoked currently.
     invoked_with: :class:`str`
@@ -75,7 +74,7 @@ class Context(discord.abc.Messageable):
         self.bot = attrs.pop('bot', None)
         self.args = attrs.pop('args', [])
         self.kwargs = attrs.pop('kwargs', {})
-        self.prefix = attrs.pop('prefix')
+        self._prefix = attrs.pop('prefix')
         self.command = attrs.pop('command', None)
         self.view = attrs.pop('view', None)
         self.invoked_with = attrs.pop('invoked_with', None)
@@ -84,6 +83,13 @@ class Context(discord.abc.Messageable):
         self.command_failed = attrs.pop('command_failed', False)
         self._state = self.message._state
 
+    @property
+    def prefix(self):
+        """:class:`str`: The cleaned up invoke prefix. i.e. mentions are ``@name`` instead of ``<@id>``."""
+        user = self.guild.me if self.guild else self.bot.user
+        pattern = re.compile(r"<@!?%s>" % user.id)
+        return pattern.sub("@%s" % user.display_name.replace('\\', r'\\'), self._prefix)
+
     async def invoke(self, *args, **kwargs):
         r"""|coro|