Re: c++ "with" keyword

[Gianni Mariani <gmariani@chaincast.com>]

Robert Dewar wrote:

>>I think you missed the point.
>>
>>The fact that this can happen - even if you make it illegal, means more 
>>maintenance.  Using it from libraries also means that simply adding a 
>>member to a library could cause untold number of users to that library 
>>have compilation errors.
>>
>>Besides, this was a "real" problem with a Pascal program I wrote many 20 
>>years ago and why I never used the 'with' keyword since.
>>    
>>
>
>A lot depends on whether you want to favor the reader or writer. Your
>complaint about having to fix existing programs when a change is made
>is about favoring the writer, but the concern about encouraging long
>name usage is about favoring the reader.
>
I favour code maintenance.  I don't like fixing bugs only to introduce a 
whole bunch of new ones that are hard to find.  This is probably my 
largest concern when it comes to writing code.

Perhaps this is why we have a large difference of opinion of what is 
more important.

>Note that this is an old discussion in the Ada world. Ada allows the USE
>clause to open up visibility, but at the expense of possible illegalities
>when new names are used. Some Ada users eschew USE completely, but others
>find USE an important capability for improving readability of code.
>
>So I find this general argument against WITH dubious. For sure it is not
>a consensus viewpoint, since in practice the world divides between those
>who dislike all implicit naming and those who find it valuable. Note that
>if such a feature is used, you presumably would prefer not to use it, but
>I don't regard that as a good argument for imposing your viewpoint.
>
>The stronger argument against adding WITH in C++ seems to be that there
>is already an adequate mechanism for providing short nicknames locally
>for long names, and WITH does not provide sufficient extra functionality
>to be worth the effort (note that compiler writers will worry that taking
>the address of something may degrade the code, so the example with the
>reference is an interesting one for the optimization crowd :-)
>  
>
Agreed.