What are functions header() & drawDatumMarker()

Experimenting with bodmer’s excellent library TFT_eSPI, I’m having trouble to locate functions header() and drawDatumMarker().
This is the error message:
src/main.cpp: In function ‘void loop()’:
src/main.cpp:70:42: error: ‘header’ was not declared in this scope
header(“Using print() method”, TFT_NAVY);
src/main.cpp:191:26: error: ‘drawDatumMarker’ was not declared in this scope
Where are these functions declared/implemented?
I’m just curious; commenting them out is a ‘solution’.

If you are referring to TFT_eSPI/Free_Font_Demo.ino at master · Bodmer/TFT_eSPI · GitHub, these functions are defined/implemented at the bottom of the code file

They are declared nowehere before that, that is, there is no prototype declaration

void header(const char *string, uint16_t color);
void drawDatumMarker(int x, int y);

which is needed for the C++ code to be valid. The referenced code works in the Arduino IDE only because of a pre-processing step that auto-generates the prototypes.

See FAQ for more.

To solve your problem, either add the function prototypes in the code before the function is called in the global context (outside of any function) or rename the file from main.cpp to main.ino to have PlatformIO also auto-generate the function prototypes like the Arduino IDE. However, you will not have IntelliSense completion on .ino files, so the first method is strongly recommended.

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