Do I understand correctly the C syntax?

Question

I have this syntax:

double (*(f(double (*)(int))))(int);

Do I understand correctly syntax above that f is function that gets pointer to function that receive int and return a double?

Answer 1

No; it's actually even more complicated than that.

cdecl.org glosses this type definition as:

declare f as function (pointer to function (int) returning double) returning pointer to function (int) returning double

In other words, the function pointed to by f takes a function pointer as an argument, and returns a function pointer. Both of those function pointers must be to functions which take an int as an argument and return a double.

You could simplify this definition a bit using an intermediate typedef as follows:

typedef double (*int_to_double_function)(int);
int_to_double_function (*f)(int_to_double_function);