The path to unity

[Andrei Alexandrescu]

Denis Koroskin wrote:
> Well put, thank you. Everyone finds this situation annoying. That's the 
> Number One problem of the D (remember "top five" poll?).
> 
> The problem as I see it is that there is an overlapping functionality in 
> Phobos and Tango (std.stream.Stream/tango.io.Conduit etc).
> The solution as I see it to redesign Phobos and Tango by removing dead 
> (buggy, unsupported) code, separating libraries functionality and 
> removing duplication.
> 
> I'd remove from Phobos:
> 
> std.
>  openrj
>  bigint (old one, by Janice)
>  regexp
>  socket
>  xml
>  much, much more (see more complete list in my previous post[1]).

These don't work all too well. But there's another issue with the 
approach you suggest. There's no dialectics. You assume that the above 
are the last word on the matter uttered by phobos. But things may be 
rewritten quite a bit for D2. Speaking of your short list above, indeed 
openrj sucks and should disappear (don't get me started). Bigint should 
be replaced by Don's implementation. Regexp should be rewritten to use 
ranges and templatized characters everywhere (you'd be able to read text 
from stdin using a regexp as a separator... anyone who's tried that 
knows that's quite a feat). Socket also needs to be rewritten to support 
ranges. Xml too, in addition to replacing the slow delegates with fast 
aliases. All of these should use the full power and expressiveness of 
D2, not transport their old design to it (as they are doing now).

> and suggest/force users use tango instead.
> 
> What's left in Phobos? A fundamental part *only*:
> 
> std.
>  math (including IEEE and BigInteger) [2]
>  range
>  traits
>  algorithm
>  contracts
>  atomics (arguably)
>  date/time (arguably)

What happened to std.random? (I just changed it to support the range 
interface; all random generators are infinite input ranges.) And what 
happened to the up-and-coming std.matrix, which is supposed to provide a 
representational lingua franca for a variety of linear algebra libraries?

> So /any/ D compiler distribution would contain:
> 
> core (druntime)
> std  (phobos)
> tango
> 
> 'druntime' would provide an essential functionality to run D programs on 
> other platforms: gc, compiler, runtime, etc.
> std - provide simple and generic functionality, that can be used in 
> conjunction (unix style): algorithm, range, contracts, math[2], some 
> helpers/utils, etc.
> tango - extended functionality: network, io (including console io), xml, 
> etc
> 
> Tango would depend on Phobos (which is now *very* tiny) and both depend 
> on druntime. I believe Tango will greatly benefit from using contracts, 
> ranges and algorithms, that are absent from it.

I think that would be great. The way I see things, however, things like 
ranges percolate through other parts of the library so strongly and so 
visibly, they are bound to decisively influence a lot more than just 
implementation internals.

> Competition is good, but only at early stages.

And then what? The Communist Utopia takes over?

> Tenders/Bids are only 
> exist to choose the best one and stick with it - the others are dropped 
> at some point. The same thing should happen with Tango/Phobos now - 
> inferior functionality should be dropped in favor or superior one. (It 
> doesn't necessarily mean that either Phobos or Tango should be dropped 
> entirely, but rather some modules - std.regexp vs. tango.text.Regex, 
> std.socket vs tango.net.*, etc).

Sure, that's great. Et que le meilleur gagne. But I'm not sure why in 
this reasoning you suppose my gonads are empty. No. They are just busy 
with other stuff. Conversely, consider I took your advice six months 
ago. That means there would have been no std.algorithm, no std.range, 
and no small but crucial language changes that made them possible 
(notably local instantiation). My opinion of the two is that they are a 
damn fine piece of design, and I don't even pat myself on the back 
because much of the design isn't mine; it's Stepanov's (in concept) and 
Walter's (in the language that allows expression of said concept). My 
perception is that others also seem to enjoy that design. So probably 
it's good I did /not/ take advice to drop phobos. But somehow now seems 
to be a better moment to do so. But if I were you I'd ask, dude, you 
mentioned containers and all that range topology stuff - anything 
interesting coming down the pike? This is an important question, because 
it's tied to a larger one - are Java containers the best that D2 can do? 
And if not, how would D2's containers look like?

> Does anyone agree/disagree with me? Anyone see other solutions? Please, 
> don't stay away from discussion.

I actually plan to stay away from this discussion henceforth. I've said 
too much already, and the first-to-last thing I need (before a bullet in 
my head) is being drawn in a political discussion. Bottom line, I'd 
completely agree with you if the situation was stagnant. But right now 
it's anything but stagnant. And that changes everything.

> PS. Andrei is about to finish TDPL. What does it say about Phobos, Tango 
> and the situation around "std libraries"?

What situation?

> What part of Phobos does it cover? I *really* hope it doesn't say much 
> about anything apart from std.range/algorithm/traits/contracts.

I think you can rest assured that the likes of std.openrj will not be 
mentioned :o|.


Andrei