Type casting in py::array_t

[tomato18463]

I note that this documentation page says

When it is invoked with a different type (e.g. an integer or a list of integers), the binding code will attempt to cast the input into a NumPy array of the requested type.

I would like to ask if this is implemented by the ensure function in this line.

Also, if I define something like:

void my_fun(py::array_t<float, py::array::c_style | py::array::forcecast> input) {
    const float* data_ptr = input.data();
    //do something 
}

I know the input will be converted to a float array with C-ordering if it is not in this format. If in any case such conversion fails, can I assume an error will always be thrown, or input will be a nullptr so the running code will report an error? Thank you very much for your help!