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digitalmars.D.learn - Small code review

reply "mist" <none none.none> writes:
Subj: http://dpaste.dzfl.pl/dfab7219

I wanted to code a small extension to phobos typetuple module to 
extend basic available operations on type tuples more on par with 
std.algorithm ones. I don't have enough practice in 
metaprogramming "D way" though and would gladly listen any 
recommendations in both improving code style and possible ways to 
implement similar things in shorter and more canonical way.

Thanks!
Jun 18 2012
parent reply "Jonathan M Davis" <jmdavisProg gmx.com> writes:
On Monday, June 18, 2012 23:41:01 mist wrote:

 Subj: http://dpaste.dzfl.pl/dfab7219
 
 I wanted to code a small extension to phobos typetuple module to
 extend basic available operations on type tuples more on par with
 std.algorithm ones. I don't have enough practice in
 metaprogramming "D way" though and would gladly listen any
 recommendations in both improving code style and possible ways to
 implement similar things in shorter and more canonical way.


Stylistically-speaking, template parameters should follow the same 
capatilization rules as everything else. If they represent types, then they 
should be PascalCase. Everything else is camelCased. And in the cases where 
it's not known (as might be the case with an alias), camelCasing is used. 
Also, if an eponymous template is going to resolve to a type it should be 
PascalCased, and if it's going to resolve to something else, it should be 
camelCased.

As for what your stuff is doing, I don't see anything blatantly wrong with it, 
but I question the wisdom of hoving filterNum be part of filter. It _is_ doing 
something similar to filter, but it's distinctly different.

You might want to take a look at std.typelist:

https://github.com/D-Programming-Language/phobos/blob/master/std/typelist.d

It's a rather old module which is not actually included in the Phobos build 
right now (I guess that it never quite made it in, and I'm not quite sure what 
we're going to do with it). It probably does some of the sort of stuff that 
you're looking for, though it takes a very different approach. If it were to be 
fully included as part of Phobos, it would need some updating (e.g. fixing how 
it names its symbols, since it doesn't always follow Phobos' naming 
conventions correctly), but it's probably worth your time to look at it if
you're really looking to manipulate TypeTuples with algorithms.

- Jonathan M Davis
Jun 18 2012
parent reply "mist" <none none.none> writes:
Could you add more details here?
What is current official position? Updating typelist.d and 
merging with typetuple.d? Keeping current one and rewriting some 
algorithms from typelist to work with current TypeTuple?
My point is exactly that it is not that much important how such 
library looks like, but it is only good if included in std lib. 
Too minor to keep as separate library, too generic to copy-paste 
needed in every project required. It is best to just "have it 
here" when you notice that some neat tuple trick can beautify 
this minor part of your code.

I'd gladly to do any stuff that needs to be done to include this 
functionality in Phobos. What are my best options?


 You might want to take a look at std.typelist:

 https://github.com/D-Programming-Language/phobos/blob/master/std/typelist.d

 It's a rather old module which is not actually included in the 
 Phobos build
 right now (I guess that it never quite made it in, and I'm not 
 quite sure what
 we're going to do with it). It probably does some of the sort 
 of stuff that
 you're looking for, though it takes a very different approach. 
 If it were to be
 fully included as part of Phobos, it would need some updating 
 (e.g. fixing how
 it names its symbols, since it doesn't always follow Phobos' 
 naming
 conventions correctly), but it's probably worth your time to 
 look at it if
 you're really looking to manipulate TypeTuples with algorithms.

 - Jonathan M Davis
Jun 20 2012
parent "Jonathan M Davis" <jmdavisProg gmx.com> writes:
On Wednesday, June 20, 2012 18:59:08 mist wrote:

 Could you add more details here?
 What is current official position? Updating typelist.d and
 merging with typetuple.d? Keeping current one and rewriting some
 algorithms from typelist to work with current TypeTuple?
 My point is exactly that it is not that much important how such
 library looks like, but it is only good if included in std lib.
 Too minor to keep as separate library, too generic to copy-paste
 needed in every project required. It is best to just "have it
 here" when you notice that some neat tuple trick can beautify
 this minor part of your code.
 
 I'd gladly to do any stuff that needs to be done to include this
 functionality in Phobos. What are my best options?


std.typelist is basically just forgotten cruft sitting in Phobos. It wasn't 
fully integrated, and I don't know how complete it really is. The file is 
sitting there, but that's about it. I think that we'd all forgotten about its 
existence until someone noticed it and brought it up in the Phobos newsgroup 
the other day. It's a cool idea, but it would probably need to be discussed in 
the main newsgroup before we did anything with it. It's one of those things
that was done earlier in D's development when Phobos' situation was less
organized.

As for your options for submitting stuff to Phobos (in general, not necessarily 
specific to this issue), if it's small stuff, then you can simply create pull 
requests on github ( https://github.com/D-Programming-Language/phobos ), and 
Phobos devs will look it over and possibly merge it. But if it's larger stuff 
(especially if it involves adding a new module), then it needs to go through 
the official review process, where it's reviewed and voted on in the main
newsgroup  before it can be included in Phobos (std.uuid is going through that
process right now).

- Jonathan M Davis
Jun 20 2012