Structure of platform specific vs non platform specific code

[rikki cattermole via Digitalmars-d-learn]

On 09/05/2017 2:53 PM, Jacob Carlborg wrote:
> On 2017-05-08 23:16, Igor wrote:
>> Hi,
>>
>> I am following Casey Muratori's Handmade Hero and writing it in DLang. I
>> got to Day 011: The Basics of Platform API Design where Casey explains
>> the best way to structure platform specific vs non-platform specific
>> code but his method cannot work in DLang since it uses modules and I am
>> wondering what would be the best way to achieve the same in DLang.
>>
>> His way is to have these files:
>> - platform.cpp (includes game.cpp directly, not game.h)
>> - game.h (declares non-platform specific data types for communicating
>> with platform layer and both game functions that platform layer needs to
>> call and platform functions that game needs to call)
>> - game.cpp (includes game.h and defines declared game functions)
>>
>> This scheme makes preprocessor actually merge all files into one but
>> logically game.* files see nothing that is platform specific.
>>
>> The best idea for DLang I have is to separate platform into two modules:
>>
>> - platform.d (contains only code that needs to call into game code so it
>> imports game.d)
>> - platformServices.d (contains only code that game needs to call but
>> wrapped in a common abstraction layer so game.d imports it)
>
> When it comes to platform specific code, one way to do it is to use one
> module per platform and then one common module that publicly imports the
> platform specific modules:
>
> module linux;
>
> module windows;
>
> module osx;
>
> module platform;
>
> version (linux)
>     public import linux;
>
> else version (Windows)
>     public import windows;
>
> else version (OSX)
>     public import osx;
>
> else
>     static assert("unsupported platform");
>
> Without having looked at the above mentioned guide (or whatever it is),
> I would say that it would make more sense that if the game module
> imports that platform module than the other way around.

Homemade hero is a video series by an experienced game dev on how to 
make a game from 0 to finish (still active!).
But yes this technique makes more sense for D then the original one.