Checking whether a variable is an integer or not [duplicate]

Answer 1

In the presence of numpy check like ..

isinstance(var, numbers.Integral)

.. (slow) or ..

isinstance(var, (int, long, np.integer))

.. in order to match all type variants like np.int8, np.uint16, ...

(Drop long in PY3)

Recognizing ANY integer-like object from anywhere is a tricky guessing game. Checking

var & 0 == 0 

for truth and non-exception may be a good bet. Similarly, checking for signed integer type exclusively:

var ^ -1 ==  -var - 1