Re: Status on Elisp and special variable handling

[Ken Raeburn]

On Oct 6, 2009, at 16:05, Daniel Kraft wrote:
> If any such value is hit when reading/setting a variable, we do the  
> needed stuff for handling aliases/foolocal variables instead of  
> doing the operation directly.  While this should work, I fear that  
> it hits performance once again...  But I do not see how we could  
> implement aliases and foolocal variables without checking on each  
> variable access if it is some special variable or not?  Maybe there  
> we could add VM support if necessary.

In the multithreaded case, I think the checks might need to be done  
every time -- one thread could call make-variable-foo-local while  
another thread is in between two accesses to the variable within a  
function.  And you also need to watch out for updating what was a non- 
foo-local variable in one thread while another makes the variable foo- 
local...

Ken