RE: [boost] a precision problem of lexical_cast

From: Jeff Garland (jeff_at_[hidden])
Date: 2002-02-03 22:47:52

Jon Wang wrote:
> I'm afraid that using template specialization might not sucess,
> because only could it deal with the floating pointer types.

By floating point types I meant both float and double.  So there would have to
be 2 specializations that call a common function. If specialization isn't
appropriate then I would suggest that always setting the precision would be an
appropriate solution.  It certainly hurts performance, but lexical_cast isn't
the highest performance solution to start with.

> ...snip....
>         string a = lexical_cast<string>(123.123456)<<setprecision(10);
>         cout<<a<<endl;
>         a = lexical_cast<string>(123.123456);

My opinion is that lexical_cast should not require the user to control the
precision at the interface.  It doesn't seem much like a "cast" when a
manipulator has to be applied.

No matter what, I think this needs to be fixed.  Kevlin you out there?

Jeff