Re: [boost] Phoenix review

Subject: Re: [boost] Phoenix review
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2008-09-26 13:24:58

Giovanni Piero Deretta wrote:

> Instead of:
> 
>     switch_(arg1)
>     [
>         case_<1>(cout << val("one") << '\n'),
>         case_<2>(cout << val("two") << '\n'),
>         default_(cout << val("other value") << '\n')
>     ]
> 
> do this:
> 
>     switch_(arg1)
>     [
>         case(1)[cout << val("one") << '\n'],
>         case(2)[cout << val("two") << '\n'],
>         default_[cout << val("other value"] << '\n')
>     ]
> 
> this allows not only runtime selection of switch case values, but it
> will also work with everything that is equally comparable:
> 
>     switch_(arg1)
>     [
>         case("one")[cout << val(1) << '\n'],
>         case("two")[cout << val(2) << '\n'],
>         default_[cout << val("other value"] << '\n')
>     ]
> 
> which IMHO is a killer feature.

In efficiency, you mean?
One dispatch is 0(1) in the number of cases, the other is 0(n).