• Max Samukha (26/26) Sep 16 2019 Please consider a project:
• Adam D. Ruppe (22/25) Sep 16 2019 Well, sort of, your code is perfectly legal and has worked since
• Max Samukha (2/9) Sep 16 2019 Thank you, Adam.

Max Samukha <maxsamukha gmail.com> writes:

Please consider a project:

src/p2/
     |---a.d
     |---b.d

in which it is desirable that the logical package tree does not 
fully correspond to the filesystem subtree:

src/p2/a.d:
module p1.p2.a;
...

src/p2/b.d:
module p1.p2.b;
import p1.p2.a;
...

dmd compiles the above structure successfully, even though the 
spec explicitly states that "The packages correspond to directory 
names in the source file path" 
(https://dlang.org/spec/module.html#module_declaration, item 2):

dmd -lib src/p2/a.d src/p2/b.d // ok

Is the spec wrong? Can the current dmd behavior be relied on?


If yes, how does one create an import tree from the structure 
like that?

'dmd -H -o- -Hdimport -op src/p1/a.d src/p2/b.d' is close, but it 
places the .di files into 'import/src/p1' directory (which is 
useless for automatic importing) instead of the expected 
'import/p1/p2'. Is it possible to achieve that without making the 
build process unreasonably complex?

Adam D. Ruppe <destructionator gmail.com> writes:

On Monday, 16 September 2019 at 07:02:04 UTC, Max Samukha wrote:
 Is the spec wrong?

Well, sort of, your code is perfectly legal and has worked since 
the beginning of D. The thing in the spec is referring to the 
assumption the compiler uses to find files not explicitly 
referenced on the build command.

import p1.p2.a;

assumes p1/p2/a.di or p1/p2/a.d.

but if you reference the module, `dmd a.d whatever/b.d`, it will 
not look up based on this assumption anymore.

 If yes, how does one create an import tree from the structure 
 like that?

I don't think dmd will create them automatically though, dmd -H 
kinda sucks, it used to just slap them down flat, now I think it 
copies the src structure, but it doesn't consider the module 
names (but it should!). You'll have to sort them yourself.

Also note the -mv option to dmd

-mv=package.module =
     Use path/filename as the source file for package.module. This 
is used when the source file path and names are not the same as 
the package and module hierarchy. The rightmost components of the 
path/filename and package.module can be omitted if they are the 
same.


which explicitly overrides the automatic assumption above, so 
import can look up any file.

Max Samukha <maxsamukha gmail.com> writes:

On Monday, 16 September 2019 at 13:13:50 UTC, Adam D. Ruppe wrote:
 On Monday, 16 September 2019 at 07:02:04 UTC, Max Samukha wrote:
 [...]

 Well, sort of, your code is perfectly legal and has worked 
 since the beginning of D. The thing in the spec is referring to 
 the assumption the compiler uses to find files not explicitly 
 referenced on the build command.

 [...]

Thank you, Adam.