[erlang-questions] '--' BIF to be used with caution?

[Richard O'Keefe]

On 6 Feb 2009, at 3:30 am, Malcolm Dowse wrote:
>
> I don't mind too much if '--' remains O(N^2). But the fact that it  
> made ERTS unresponsive is more of a worry, to me, because this  
> seemed to go against the spirit of the language.

Since -- is seriously inefficient (you can easily get O(|l1|.lg|l2|)
in pure Erlang, so what's the point of doing O(|l1|.|l2|) in C?),
why not fix the blocking issue by just turning it into ordinary
Erlang code?  Is there any reason why an operator can't be implemented
in Erlang?