a possibility to redefine built-in GHCi commands

[Peter Hercek]

Hi GHCi users,

I would like to be able to redefine the built-in GHCi commands. The idea 
is that when searching for a command the user defined commands would be 
searched first and only then the built-in commands would be searched. If 
  user wants to invoke a built-in command regardless of user defined 
commands he/she would need to start it with two colons (instead of one).

It is an user interface change which may break some scripts, but it 
would allow to provide different default behavior.
For example:
* when I use GhciExt I want all my ":continue" commands to be actually 
":x :continue"
* it would allow to specify different order of searching for abbreviated 
commands as the default one
* it would allow to specify different default switches for builtin commands

Would such a change be merged upstream if I would provide a patch?

Peter.