www.digitalmars.com         C & C++   DMDScript  

digitalmars.D.learn - How to use the -I command line switch?

reply tipdbmp <email example.com> writes:
// C:\libs\my_module.d
module my_module;
void foo() {}

// main.d
module main;
import my_module;

void main() {
     foo();
}

Running dmd with:
     dmd -IC:\libs main.d my_module.d

I get:
     Error: module my_module is in file 'my_module.d' which cannot 
be read
     import path[0] = C:\libs
     import path[1] = 
path\to\dmd\D\dmd2\windows\bin\..\..\src\phobos
     import path[2] = 
path\to\dmd\D\dmd2\windows\bin\..\..\src\druntime\import
Jan 03 2018
next sibling parent reply jmh530 <john.michael.hall gmail.com> writes:
On Wednesday, 3 January 2018 at 12:21:28 UTC, tipdbmp wrote:

 // C:\libs\my_module.d
 module my_module;
 void foo() {}

 // main.d
 module main;
 import my_module;

 void main() {
     foo();
 }

 Running dmd with:
     dmd -IC:\libs main.d my_module.d

 I get:
     Error: module my_module is in file 'my_module.d' which 
 cannot be read
     import path[0] = C:\libs
     import path[1] = 
 path\to\dmd\D\dmd2\windows\bin\..\..\src\phobos
     import path[2] = 
 path\to\dmd\D\dmd2\windows\bin\..\..\src\druntime\import



dmd main.d C:\libs\my_module.d

I usually use dub for this type of thing...
Jan 03 2018
parent reply tipdbmp <email example.com> writes:
 dmd main.d C:\libs\my_module.d


That does not use the -I switch.

It compiles if I specify the full path to my_module.d:
     dmd -IC:\libs main.d C:\libs\my_module.d

I don't understand the error message though.
Jan 03 2018
next sibling parent jmh530 <john.michael.hall gmail.com> writes:
On Wednesday, 3 January 2018 at 17:10:22 UTC, tipdbmp wrote:

 dmd main.d C:\libs\my_module.d


 That does not use the -I switch.

 It compiles if I specify the full path to my_module.d:
     dmd -IC:\libs main.d C:\libs\my_module.d

 I don't understand the error message though.


I tried a few other options, but I don't use it enough to know 
the trick to get it working. I tend to use either dub, setting 
the path environmental variables, or the absolute path. Hopefully 
someone else can let you know. If it's a bug, it should be in 
bugzilla, but sometimes I just assume I screwed something up.
Jan 03 2018
prev sibling parent reply =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
On 01/03/2018 09:10 AM, tipdbmp wrote:

 dmd main.d C:\libs\my_module.d


 That does not use the -I switch.
 
 It compiles if I specify the full path to my_module.d:
      dmd -IC:\libs main.d C:\libs\my_module.d
 
 I don't understand the error message though.
 


-I is for import directives only. imports are needed to compile the 
importing module. All other modules still need to be compiled themselves 
and added to the program either as individual .o files or as libraries 
(e.g. .a, .lib, etc.).

The method you've shown is a shorthand for "compile each to .o and add 
each to the program."

Working as expected... :)

Ali
Jan 03 2018
next sibling parent reply Tony <tonytdominguez aol.com> writes:
On Wednesday, 3 January 2018 at 18:35:21 UTC, Ali Çehreli wrote:

 On 01/03/2018 09:10 AM, tipdbmp wrote:

 dmd main.d C:\libs\my_module.d


 That does not use the -I switch.
 
 It compiles if I specify the full path to my_module.d:
      dmd -IC:\libs main.d C:\libs\my_module.d
 
 I don't understand the error message though.
 


 -I is for import directives only. imports are needed to compile 
 the importing module. All other modules still need to be 
 compiled themselves and added to the program either as 
 individual .o files or as libraries (e.g. .a, .lib, etc.).

 The method you've shown is a shorthand for "compile each to .o 
 and add each to the program."

 Working as expected... :)


What about the error message? If -I is only for DMD finding 
"import ..." files, and not files on the command line, why does 
DMD list what was in the -I "where to look for import directives" 
when saying that it can't find a command-line file? It says that 
it can't locate my_module.d and then lists the directory that 
my_module.d is in.
Jan 03 2018
parent =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
On 01/03/2018 01:42 PM, Tony wrote:

 On Wednesday, 3 January 2018 at 18:35:21 UTC, Ali Çehreli wrote:



 Working as expected... :)


 What about the error message? If -I is only for DMD finding "import ..."
 files, and not files on the command line, why does DMD list what was in
 the -I "where to look for import directives" when saying that it can't
 find a command-line file? It says that it can't locate my_module.d and
 then lists the directory that my_module.d is in.


Yeah, there's definitely a problem there.

It's possible that the compiler is acting like this: Because there is 
already my_module.d on the command line, it assumes that main's 'import 
my_module' must mean that file. Because there is no such file in the 
local directory, it errors out by using a generic error message 
function, which does not explain the situation well.

I made that all up but I bet it's something like that. :)

Ali
Jan 03 2018
prev sibling parent reply jmh530 <john.michael.hall gmail.com> writes:
On Wednesday, 3 January 2018 at 18:35:21 UTC, Ali Çehreli wrote:

 -I is for import directives only. imports are needed to compile 
 the importing module. All other modules still need to be 
 compiled themselves and added to the program either as 
 individual .o files or as libraries (e.g. .a, .lib, etc.).

 The method you've shown is a shorthand for "compile each to .o 
 and add each to the program."

 Working as expected... :)

 Ali


Is there any way to re-write the documentation so its clearer? 
I've been confused by this before as well...
Jan 03 2018
parent reply Seb <seb wilzba.ch> writes:
On Wednesday, 3 January 2018 at 21:51:07 UTC, jmh530 wrote:

 On Wednesday, 3 January 2018 at 18:35:21 UTC, Ali Çehreli wrote:

 -I is for import directives only. imports are needed to 
 compile the importing module. All other modules still need to 
 be compiled themselves and added to the program either as 
 individual .o files or as libraries (e.g. .a, .lib, etc.).

 The method you've shown is a shorthand for "compile each to .o 
 and add each to the program."

 Working as expected... :)

 Ali


 Is there any way to re-write the documentation so its clearer? 
 I've been confused by this before as well...


Which documentation are you referring to? If it's the 
specification, just click "edit".
Jan 03 2018
parent jmh530 <john.michael.hall gmail.com> writes:
On Wednesday, 3 January 2018 at 22:52:10 UTC, Seb wrote:

 Which documentation are you referring to? If it's the 
 specification, just click "edit".


I know how to edit it. I just don't know how to word it so that 
it isn't so confusing.
Jan 03 2018
prev sibling parent Tony <tonytdominguez aol.com> writes:
On Wednesday, 3 January 2018 at 12:21:28 UTC, tipdbmp wrote:

 // C:\libs\my_module.d
 module my_module;
 void foo() {}

 // main.d
 module main;
 import my_module;

 void main() {
     foo();
 }

 Running dmd with:
     dmd -IC:\libs main.d my_module.d

 I get:
     Error: module my_module is in file 'my_module.d' which 
 cannot be read
     import path[0] = C:\libs
     import path[1] = 
 path\to\dmd\D\dmd2\windows\bin\..\..\src\phobos
     import path[2] = 
 path\to\dmd\D\dmd2\windows\bin\..\..\src\druntime\import


As has already been mentioned, the -I is not used for 
command-line files. Just compiling (-c option) shows that the -I 
is enough for DMD to find the import file:

dmd -c main.d -Ic:\libs

successfully compiles main.d into main.obj

To do a full compile and link of main without compiling 
my_module.d each time:

C:\libs>dmd -lib -ofmy_module.lib my_module.d

creates "my_module.lib". Then use it to link with in main.d 
compile/link:

C:\code\d\forum>dmd main.d -Ic:\libs -Llib c:\libs\my_module
OPTLINK (R) for Win32  Release 8.00.17
Copyright (C) Digital Mars 1989-2013  All rights reserved.
http://www.digitalmars.com/ctg/optlink.html
OPTLINK : Warning 9: Unknown Option : NOILIB


main.exe is created even though there is a mysterious warning.
Jan 03 2018