Re: [boost] std::map::find() wrapper

Subject: Re: [boost] std::map::find() wrapper
From: Olaf van der Spek (ml_at_[hidden])
Date: 2011-05-04 07:04:38

On Wed, May 4, 2011 at 12:50 PM, Robert Jones <robertgbjones_at_[hidden]> wrote:
> On Wed, May 4, 2011 at 11:33 AM, Olaf van der Spek <ml_at_[hidden]> wrote:
>
>> On Wed, May 4, 2011 at 9:37 AM, Robert Jones <robertgbjones_at_[hidden]>
>> wrote:
>> > On Tue, May 3, 2011 at 8:52 PM, Olaf van der Spek <ml_at_[hidden]> wrote:
>> >
>> >> On Tue, May 3, 2011 at 6:57 PM, Robert Jones <robertgbjones_at_[hidden]>
>> >> wrote:
>> >> >  I'd prefer to see it return a boost::optional<T&>
>> >>
>> >> What's the benefit?
>> >>
>> >
>> > Simply that the difficulty you're addressing is the possibility that
>> there's
>> > no
>> > value to return. Boost.optional expresses that directly.
>>
>> Returning NULL works just as well.
>> Using a raw pointer also allows you to write string* ptr = find_ptr().
>> Using Boost Optional would make that longer.
>>
>>
> You'd have to write optional<string> s = find_ptr(); //Now misnamed of
> course!

boost::optional
Shouldn't it be string&?

> Either way, at some point you'd have to check the value was usable before
> using it.

Sure, but that can be done just as well with a pointer.
Boost Optional is targeted at functions that return by value.

What's the best way to get this wrapper into Boost?

Olaf