Re: [Boost-build] CVS: boost/tools/build/new property.jam,1.31,1.32

From: David Abrahams (gclbb-jamboost_at_[hidden])
Date: 2003-05-10 22:46:37

Vladimir Prus <ghost_at_[hidden]> writes:

> David Abrahams wrote:
>
>> Modified Files:
>> property.jam
>> Log Message:
>> improve error reporting
>
>> + # need to do this here to get reasonable error messages for
>> + # unrecognized implicit features.
>> + validate $(p) ;
>> +
>
> A small design note. Ultimately, it's better to avoid calls to "validate" at 
> all. All properties should be represented as instances of property-set class 
> and validation will happen only when such an instances is created from user 
> input. E.g. a new rule property-set.create-with-validation can be introduced.

Why should we provide an option to not validate on creation?

> After that, property-set instances is guaranteed to have only valid
> properties and all operations with it will leave it valid -- thus,
> "validate" must be called only in few places.
>
> What do you think?

In principle, I agree that bottlenecking error checking through a
very few routines is a great idea.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com