C++ - Integration of CLIPS (rule engine)

Question

I'm trying to integrate CLIPS into my C++ application (QT-project). I already have included the source and header files to the projects. I'm now trying to compile the downloaded source code to see if my basic call within main is working. I'm stuck with the error codes below and do not know to solve them. I also do not want to change the source code of CLIPS which should be just integrated.

void *env;

env = CreateEnvironment();



// The file hello.clp must be in the same directory
// as the CLIPS executable or you must specify the
// full directory path as part of the file name.

EnvLoad(env, "hello.clp");
EnvReset(env);
EnvRun(env,-1);
DestroyEnvironment(env);

Compiling the code leads to the errors:

...\function\core\object.h:113: Fehler: expected unqualified-id before ',' token SLOT_DESC *slots,

and

...\function\core\object.h:211: Fehler: expected unqualified-id before ';' token *slots;

The error points to the code:

struct instance
  {
    ....
   INSTANCE_SLOT **slotAddresses,
                 *slots;
  };

and

struct defclass
  {
    ...
   SLOT_DESC *slots,
             **instanceTemplate;
    ...
  };

This is not my own code I'm just trying to use the functionality provided by CLIPs and integrate it into my own application. CLIPS Programming Guide

Qt defines a global macro `slots` that interferes with the variable names CLIPS chose. . See this question: [Qt macro keywords cause name collisions](https://stackoverflow.com/questions/22188432/qt-macro-keywords-cause-name-collisions) — Botje, May 25 '20 at 13:42

score 0 · Answer 1 · edited Jun 20 '20 at 09:12

0

Try this

1.1 C++ Compatibility

The CLIPS source code can be compiled using either an ANSI C or C++ >compiler. To make CLIPS API calls from a C++ program, it is usually easier to do the integration by compiling the CLIPS source files as C++ files. This removes the need to make an extern "C"declaration in your C++ program for the CLIPS APIs. Some compilersallow you to specify the whether a file should be compiled as C or C++ code based on the file extension. Other compilersallow you to explicitly specify which compiler to use regardless of the extension

(e.g. in gcc the option “-x c++” will compile .c files as C++ files)

For compilers that exclusively use the file extension to determine whether the >file should be compiled as a C or C++ code,it's necessary to changethe .c >extension of the CLIPS source files to a .cppextension.

edited Jun 20 '20 at 09:12

Community

1
1

answered May 25 '20 at 13:40

lupaulus

358
5
22

Hey I already wrote a script which just changes all *.c to *.cpp therefore QT should normally compile it as c++, shouldn't it? – s kop May 25 '20 at 13:45
Using Qtcreator ? Look at your build config – lupaulus May 25 '20 at 13:51
Changing the .c in .cpp as for me isn't a good idea – lupaulus May 25 '20 at 13:51

C++ - Integration of CLIPS (rule engine)

1 Answers1