Duda, define variable with smart compilation

arixtoteles09 · February 12, 2023, 11:46am

I want to create a generic code, that depending on the parameters that I pass with #define, I declare some variables or others, I think it is something like this, but the answer is that the variables are not defined, Main code:

#include "ESP_VarDef.h"

#define VAR_V00 true
#define VAR_X00 true
#define VAR_X01 true

void setup(){
  Serial.begin(115200);
}
void loop(){
  Serial.println("----------");
  Serial.println(VAR_V00A);
  Serial.println(VAR_X00A);
  Serial.println(VAR_X01A);
  Serial.println("----------");
}

secondary code:

#if defined(VAR_V00)
  int    VAR_V00A = 0        ;//device 0: Minute day
  bool   VAR_V01A = 0        ;//device 0: Status led
#endif
#if defined(VAR_X00)
  int    VAR_X00A = 0        ;//device 1: Time mode
  int    VAR_X00B = 0        ;//device 1: Time start
  int    VAR_X00C = 0        ;//device 1: Time end
  int    VAR_X00D = 0        ;//device 1: Time mode
  int    VAR_X00E = 0        ;//device 1: Time start
  int    VAR_X00F = 0        ;//device 1: Time end
#endif
#if defined(VAR_X01)
  bool   VAR_X01A = 0        ;//device 2: RGB state
  String VAR_X01B = "000000" ;//device 2: RGB color
#endif

how could i do it?

J-M-L · February 12, 2023, 11:48am

How is the "secondary code" injected in the .ino ?

the .ino cannot print the variables if they do not exist, so your print() should also have an #ifdef

arixtoteles09 · February 12, 2023, 11:51am

Yes, I am aware, when I copied it, a line remained...

arixtoteles09 · February 12, 2023, 11:52am

It's already corrected, sry

J-M-L · February 12, 2023, 11:56am

you could try something like this

with a proper .h and .cpp
and have functions that are abstracting your configuration in the .cpp

UKHeliBob · February 12, 2023, 11:59am

#if defined(VAR_V00)

Because you have #defined VAR_V00 as true the compiler will see

if defined(true)

which will return true because the value of true is #defined as part of the behind the scenes processing in Arduino

Even if you #defined VAR_V00 as false then

if defined(false)

will also return true for the same reason

gcjr · February 12, 2023, 12:03pm

can you describe your application where you have a varying # of variables as well as varying logic that operations on those variables?

or do you just have sub-sets of variables/logic?

arixtoteles09 · February 12, 2023, 12:14pm

When I put this code in the arduino ide, it tells me that Serial is not defined, I don't understand it...

J-M-L · February 12, 2023, 12:33pm

Post thé 3 files as you created them in the IDE and the file names

Which arduino are you using?

arixtoteles09 · February 12, 2023, 12:45pm

Arduino IDE 1.8.19

demo.ino

#include "demo.h"

void setup() {
  Serial.begin(115200);
  printAllVariables();
}

void loop() {}

demo.h

#ifndef _SECONDARY_H_
#define _SECONDARY_H_

#include <Arduino.h>

#define VAR_V00 true
#define VAR_X00 true
#define VAR_X01 true

void printAllVariables();

#endif

demo.cpp

#if VAR_V00
int    VAR_V00A = 0        ;//device 0: Minute day
bool   VAR_V01A = 0        ;//device 0: Status led
#endif

#if VAR_X00
int    VAR_X00A = 0        ;//device 1: Time mode
int    VAR_X00B = 0        ;//device 1: Time start
int    VAR_X00C = 0        ;//device 1: Time end
int    VAR_X00D = 0        ;//device 1: Time mode
int    VAR_X00E = 0        ;//device 1: Time start
int    VAR_X00F = 0        ;//device 1: Time end
#endif

#if VAR_X01
bool   VAR_X01A = 0        ;//device 2: RGB state
String VAR_X01B = "000000" ;//device 2: RGB color
#endif

void printAllVariables() {
  Serial.println("----------");

#if VAR_V00
  Serial.println(VAR_V00A);
#endif

#if VAR_X00
  Serial.println(VAR_X00A);
#endif

#if VAR_X01
  Serial.println(VAR_X01A);
#endif

  Serial.println("----------");
}

gfvalvo · February 12, 2023, 12:52pm

Post the actual and complete error message, not your interpretation of it.

arixtoteles09 · February 12, 2023, 1:31pm

C:\Users\Arixt\Desktop\demo\demo.cpp: In function 'void printAllVariables()':
demo.cpp:21:3: error: 'Serial' was not declared in this scope
   21 |   Serial.println("----------");
      |   ^~~~~~
exit status 1
'Serial' was not declared in this scope

gfvalvo · February 12, 2023, 1:35pm

arixtoteles09:

C:\Users\Arixt\Desktop\demo\demo.cpp: In function 'void printAllVariables()':
demo.cpp:21:3: error: 'Serial' was not declared in this scope
   21 |   Serial.println("----------");
      |   ^~~~~~
exit status 1
'Serial' was not declared in this scope

Your "demo.cpp" needs:

#include "demo.h"

J-M-L · February 12, 2023, 1:46pm

my secondary.cpp was including

#include "secondary.h"

this is how I indirectly include Arduino.h which ensures the usual Arduino functions and classes are known - such as Serial

arixtoteles09 · February 12, 2023, 3:22pm

I have managed to get my code to compile without errors, but the result in the terminal is this:

--------------------
--------------------
--------------------
--------------------
--------------------
--------------------

the files are, "ESP_VarDef.ino":

#include <ESP_VarDef.h>

#define VAR_A01XX true
#define VAR_A02XX true
#define VAR_A03XX true

void setup(){
  Serial.begin(115200);
}
void loop(){
  ESP_VarPrint();
  delay(1000);
}

"ESP_VarDef.h":

#ifndef _ESP_VarDef_H_
#define _ESP_VarDef_H_
#include <Arduino.h>
void ESP_VarPrint();
#endif

"ESP_VarDef.cpp":

#include <ESP_VarDef.h>

#if VAR_A01XX
  int    VAR_A0100 = 0        ;//device 1: Minute day
  bool   VAR_A0101 = 0        ;//device 1: Status led
#endif
#if VAR_A02XX
  int    VAR_A0200 = 0        ;//device 1: Time mode
  int    VAR_A0201 = 0        ;//device 1: Time start
  int    VAR_A0202 = 0        ;//device 1: Time end
  int    VAR_A0203 = 0        ;//device 1: Time mode
  int    VAR_A0204 = 0        ;//device 1: Time start
  int    VAR_A0205 = 0        ;//device 1: Time end
#endif
#if VAR_A03XX
  bool   VAR_A0300 = 0        ;//device 2: RGB state
  String VAR_A0301 = "000000" ;//device 2: RGB color
#endif

void ESP_VarPrint(){
  Serial.println("--------------------");
  #if VAR_A01XX
    Serial.println("VAR_A0100" + String(VAR_A0100));
    Serial.println("VAR_A0101" + String(VAR_A0101));
  #endif
  #if VAR_A02XX
    Serial.println("VAR_A0200" + String(VAR_A0200));
    Serial.println("VAR_A0201" + String(VAR_A0201));
    Serial.println("VAR_A0202" + String(VAR_A0202));
    Serial.println("VAR_A0203" + String(VAR_A0203));
    Serial.println("VAR_A0204" + String(VAR_A0204));
    Serial.println("VAR_A0205" + String(VAR_A0205));
  #endif
  #if VAR_A03XX
    Serial.println("VAR_A0300" + String(VAR_A0300));
    Serial.println("VAR_A0301" + String(VAR_A0301));
  #endif
}

gfvalvo · February 12, 2023, 3:26pm

arixtoteles09:

I have managed to get my code to compile without errors, but the result in the terminal is this:
--------------------
--------------------
--------------------
--------------------
--------------------
--------------------

You have these #defines in the .ino file so they won't be seen when ESP_VarDef.cpp is compiled. Put them in ESP_VarDef.h.

#define VAR_A01XX true
#define VAR_A02XX true
#define VAR_A03XX true

arixtoteles09 · February 12, 2023, 3:32pm

but that would force me to edit the .h for each case, couldn't they be redirected in some way? that is to say, give the .ino the value and that the .h use it?

gfvalvo · February 12, 2023, 3:39pm

No.

J-M-L · February 12, 2023, 4:46pm

You could have a config.h that has the #define and the ESP_VarDef.h. would include that config.h

config.h

#define VAR_A01XX true
#define VAR_A02XX true
#define VAR_A03XX true

ESP_VarDef.h

#ifndef _ESP_VarDef_H_
#define _ESP_VarDef_H_
#include <Arduino.h>
#include "config.h"

void ESP_VarPrint();
#endif

Then you would have to edit that configuration file, it may seem more natural

arixtoteles09 · February 12, 2023, 6:51pm

ok, that's a good idea, but if the Config.h file is in the program folder and the library is in its own folder (...\Documents\Arduino\libraries\ESP_VarDef), how can I reference the file?

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Duda, define variable with smart compilation

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