Typedef error in tab

Projects Programming
1

I have boiled a compilation problem I am having down to the following code...

I get the following compiler error...
Screenshot 2022-01-03 at 14.00.23

... for the following code:

Main Project file...
void setup(){}
void loop(){}

A second tab...
typedef int T;
void f(T t1){};

If the contents of the second tab are placed in the main project file the sketch compiles.

Any help would be appreciated.

2

What is the full name of the file in the second tab ?

ts200010 3

Screenshot 2022-01-03 at 14.10.58

4

What is the full name of the file in the second tab ?

5

A08Examples.ino

6

Also the following code does not throw errors declaring T's before the function declaration. The function declaration attracts the same errors as above.

typedef int T;
T t;
T t1=1;
void f(T t){};

Comment out the function declaration and the scrap of code compiles fine.

A function declaration will start a new scope for the parameter names but it should inherit the declarations from the surrounding scope. T should still be in scope.... This is probably to do with how the IDE pieces together the pieces of code to make a compilation unit.

I am going to look for a temporary file that is actually sent to the compiler....

7

It's the automatically generated prototype. You are getting:

void f(T t1);  // Auto generated. T not defined.
void setup(){}
void loop(){}

typedef int T;
void f(T t1){};

To fix it, add a manual prototype after the declaration of 'T':

void setup(){}
void loop(){}

typedef int T;
void f(T t1);  // This keeps the IDE from generating a prototype at the top of the (combined) file.
void f(T t1){};

Another option is to change the extension from .ino to .cpp. The file will be compiled separately and not have prototypes generated.

8

OK ... l get it. Many many thanks.