The path to unity

[Chad J]

Jarrett Billingsley wrote:
> On Fri, Feb 6, 2009 at 6:53 PM, Chad J
> <gamerchad at __spam.is.bad__gmail.com> wrote:
>> another wall of text.
> 
> I'll have to say that I wholeheartedly disagree.  (You knew this was coming.)
> 
> Even if they use a common runtime and small common core, nothing is
> compatible between the user portions of the libraries. Sure, you'll be
> able to install Phobos and Tango side-by-side without issue, but
> honestly, why would you want to do that? Oh, I see - you're using two
> third-party libraries, one based on Tango and one on Phobos. But.. it
> still doesn't solve the problem. The one library wants std.date.Dates
> and the other wants tango.time.Time.Times. Or std.stream.Streams vs.
> tango.io.Conduits. The split between the libraries has just moved from
> the runtime level up to the user level. Even if they use the same
> runtime, Phobos and Tango cannot be used with one another.
> 

But they CAN be used together, Tangobos style.  There is one bad problem
with exclusive features like IO handling tripping over each other a bit.
 That is annoying.

The other possible issue is when passing types between the user level
and the third party lib: which std lib type to use?  I'd like to know
just how often std lib types are used in library interfaces.  I suspect
it's almost never.  Even then, it wouldn't stop compilation if you have
something like Tangobos.

> Newbs are confused when they first come to the language and find out
> there are two standard libraries, and that they have to choose which
> one to use.  Worse, if you use one standard library, there's a whole
> set of third-party libraries that you just can't use.  The alternative
> is for library writers to support both libraries by writing a
> compatibility layer - their own standard library! This is just
> ridiculous. Not only do D users have to deal with the first-order
> problem of which standard library they should use, but they also have
> to deal with the second-order problem of which third-party libraries
> support which standard library.
> 
> It doesn't matter how you sugarcoat it.  It doesn't give people
> choices, it gives people _a_ choice - which "version" of D they want
> to use: Phobos D or Tango D.  As a library writer, I can't say that I
> find that situation, or the idea of writing a compatibility layer for
> all but the simplest of functionality, very attractive.

I do agree that this situation sucks.  Library writers need to be able
to pick one and be confident that people who prefer the other library
will still be able to use their code and with no odd quirks or gotchas
either.  This is why I see the two standard libraries becoming
completely non-exclusive, thus allowing programs to link against and use
both at the same time.