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digitalmars.D.learn - Module import incompatibility

reply frame <frame86 live.com> writes:
I'm sure it was asked before but can't find the thread:

How to deal best with an older library that uses the same class 
name as module name?
I get a lot of

`Error: module ABC from file ...ABC.d must be imported with 
'import ABC'`

Do I need to rename all modules?
Aug 31 2021
parent reply bauss <jj_1337 live.dk> writes:
On Tuesday, 31 August 2021 at 12:26:28 UTC, frame wrote:

 I'm sure it was asked before but can't find the thread:

 How to deal best with an older library that uses the same class 
 name as module name?
 I get a lot of

 `Error: module ABC from file ...ABC.d must be imported with 
 'import ABC'`

 Do I need to rename all modules?


The problem is that the file doesn't have a module statement so 
the compiler tries to resolve the module name from the import but 
is unable to resolve that properly.

The fix here is the module must have a module statement but since 
it's a library then you probably need to go into said library and 
fix it manually.

There's really no other fix I believe.
Aug 31 2021
parent reply frame <frame86 live.com> writes:
On Tuesday, 31 August 2021 at 12:37:51 UTC, bauss wrote:

 On Tuesday, 31 August 2021 at 12:26:28 UTC, frame wrote:

 I'm sure it was asked before but can't find the thread:

 How to deal best with an older library that uses the same 
 class name as module name?
 I get a lot of

 `Error: module ABC from file ...ABC.d must be imported with 
 'import ABC'`

 Do I need to rename all modules?


 The problem is that the file doesn't have a module statement so 
 the compiler tries to resolve the module name from the import 
 but is unable to resolve that properly.


No, it has one, eg:

```d
module cairo.PdfSurface;
```

but the filename is PdfSurface.d and class name also :\
Aug 31 2021
next sibling parent reply Paul Backus <snarwin gmail.com> writes:
On Tuesday, 31 August 2021 at 12:57:33 UTC, frame wrote:

 No, it has one, eg:

 ```d
 module cairo.PdfSurface;
 ```

 but the filename is PdfSurface.d and class name also :\


You can use a selective import:

```d
import cairo.PdfSurface: PdfSurface;
```
Aug 31 2021
parent frame <frame86 live.com> writes:
On Tuesday, 31 August 2021 at 13:03:54 UTC, Paul Backus wrote:

 On Tuesday, 31 August 2021 at 12:57:33 UTC, frame wrote:

 No, it has one, eg:

 ```d
 module cairo.PdfSurface;
 ```

 but the filename is PdfSurface.d and class name also :\


 You can use a selective import:

 ```d
 import cairo.PdfSurface: PdfSurface;
 ```


Damn it's working - I swear I tried that before.
I believe sometimes VsCode doesn't really updating my files.

Thx.
Aug 31 2021
prev sibling parent reply Steven Schveighoffer <schveiguy gmail.com> writes:
On 8/31/21 8:57 AM, frame wrote:

 On Tuesday, 31 August 2021 at 12:37:51 UTC, bauss wrote:

 On Tuesday, 31 August 2021 at 12:26:28 UTC, frame wrote:

 I'm sure it was asked before but can't find the thread:

 How to deal best with an older library that uses the same class name 
 as module name?
 I get a lot of

 `Error: module ABC from file ...ABC.d must be imported with 'import 
 ABC'`

 Do I need to rename all modules?


 The problem is that the file doesn't have a module statement so the 
 compiler tries to resolve the module name from the import but is 
 unable to resolve that properly.


 
 No, it has one, eg:
 
 ```d
 module cairo.PdfSurface;
 ```
 
 but the filename is PdfSurface.d and class name also :\
 
 


Are you sure this is the problem? `PdfSurface` is not a valid identifier 
here except for the class. In order to access the package, you need to 
use `cairo.PdfSurface`.

Tango was full of stuff like this, and it worked fine *as long as* it 
wasn't a top-level module.

-Steve
Aug 31 2021
next sibling parent reply Paul Backus <snarwin gmail.com> writes:
On Tuesday, 31 August 2021 at 14:09:01 UTC, Steven Schveighoffer 
wrote:

 Are you sure this is the problem? `PdfSurface` is not a valid 
 identifier here except for the class. In order to access the 
 package, you need to use `cairo.PdfSurface`.


Must've changed since you last checked:

```d
// main.d
import example;

void main()
{
     // Error: incompatible types for `(module example) == (42)`: 
`void` and `int`
     assert(example == 42);
}
```
```d
// example.d
int example = 42;
```

https://run.dlang.io/is/SpEZNF
Aug 31 2021
parent Steven Schveighoffer <schveiguy gmail.com> writes:
On 8/31/21 11:17 AM, Paul Backus wrote:

 On Tuesday, 31 August 2021 at 14:09:01 UTC, Steven Schveighoffer wrote:

 Are you sure this is the problem? `PdfSurface` is not a valid 
 identifier here except for the class. In order to access the package, 
 you need to use `cairo.PdfSurface`.


 
 Must've changed since you last checked:
 
 ```d
 // main.d
 import example;
 
 void main()
 {
      // Error: incompatible types for `(module example) == (42)`: `void` 
 and `int`
      assert(example == 42);
 }
 ```
 ```d
 // example.d
 int example = 42;
 ```
 
 https://run.dlang.io/is/SpEZNF
 


That is a top-level module that has an equivalent name inside. I did say 
"*as long as* it wasn't a top-level module"

```d
// main.d
import pkg.mod;

void main()
{
    assert mod = 42;
}

// example.d
module pkg.mod;
int mod = 42;
```

works fine

https://run.dlang.io/is/sQ4Bsa

This is why I always try to use a top-level package instead of a module 
(especially with a common name).

-Steve
Aug 31 2021
prev sibling parent frame <frame86 live.com> writes:
On Tuesday, 31 August 2021 at 14:09:01 UTC, Steven Schveighoffer 
wrote:


 Are you sure this is the problem? `PdfSurface` is not a valid 
 identifier here except for the class. In order to access the 
 package, you need to use `cairo.PdfSurface`.

 Tango was full of stuff like this, and it worked fine *as long 
 as* it wasn't a top-level module.

 -Steve


Ah, now I see the problem. It was imported with an additional 
top-level package path and that caused my confusion because the 
compiler shows the right path in the error and also the IDE sees 
the package with this top-level path, so it seems right but the 
module declaration doesn't match, of course.

Thanks.
Aug 31 2021