Re: [boost] [optional] std::tr2::optional

Subject: Re: [boost] [optional] std::tr2::optional
From: paul Fultz (pfultz2_at_[hidden])
Date: 2011-11-18 14:36:49

>I provide a list of
>modifications that I could think of. What is your opinion?
This is more of an addition to your list, but I think adding 

the | operator for getting the optional value or a default value would be nice.
For example:

optional<double> safe_sqrt(double x)
{
    if (x < 0) return none;
    else return sqrt(x);
}

double x = safe_sqrt(4) | 0; //x = 4
double y = safe_sqrt(-1) | 0; //y = 0 

I dont know if this is possible for tr2, but would be really nice
addition in the future. Especially, since a lot of times i just 
want a default value if the optional value doesn't exist.