Proposal: fixing the 'pure' floating point problem.

[Andrei Alexandrescu]

Walter Bright wrote:
> Don wrote:
>> The math functions need to work for any rounding mode, not just the 
>> default mode. They also set the status flags correctly. In fact, they 
>> are almost the only functions where this matters!
> 
> Ok, then std.math functions cannot be pure in either your or my 
> proposal, so I'm not seeing the advantage of yours.

Ok, I need to clear some ignorance on my part:

1. Is it usual to change the FP flags in an application multiple times, 
or not? (I never changed them, so please be easy on me.)

2. Is one FP flag setup much more often used than others? If so, we 
could define pure functions assuming the often-used setup and then some 
impure functions using any other setup.


Andrei