naming

I try to avoid 1-letter variable names, unless it are x, y, z for coordinates, or i during an iteration, so I would rename f to float_value or something, but that is a matter of taste.

short_circuit

if value is an int or StrictInt already, you can return early. This way, you also

failing test-cases

there are a few cases that fail the current implementation that are integers

StrictInt(0)
StrictInt(0.0)
StrictInt(3 + 0j)
StrictInt('3 + 0j')

fixing the first is as easy as changing if not f: to if f is None

#Complex

adding support for complex is rather easy, and eliminates the need to call float

class StrictInt(int):
 def __new__(cls, value, *args, **kwargs):
 # type: (Union[int, float, str], Any, Any) -> int
 
 if isinstance(value, (int, StrictInt)):
 return super(StrictInt, cls).__new__(cls, value)
 if isinstance(value, str):
 value = value.replace(' ', '')
 elif not isinstance(value, (float, complex)):
 type_str = str(type(value)).replace("<class '", "").replace("'>", "")
 raise TypeError("Cannot convert type '{type}' to strict integer".format(type=type_str))
 
 try:
 complex_value = complex(value)
 except ValueError:
 raise ValueError("Cannot convert a non-number to a strict integer.")
 if complex_value.imag:
 raise ValueError('Cannot convert complex number with imaginary part')
 
 float_value = complex_value.real
 if not float_value.is_integer():
 raise ValueError("Cannot convert value due to non-integer parts.")
 return super(StrictInt, cls).__new__(cls, int(float_value))

Python 2

If you want to include python 2, unicode should also be accepted as type

naming

I try to avoid 1-letter variable names, unless it are x, y, z for coordinates, or i during an iteration, so I would rename f to float_value or something, but that is a matter of taste.

short_circuit

if value is an int or StrictInt already, you can return early. This way, you also

failing test-cases

there are a few cases that fail the current implementation that are integers

StrictInt(0)
StrictInt(0.0)
StrictInt(3 + 0j)
StrictInt('3 + 0j')

fixing the first is as easy as changing if not f: to if f is None

Complex

adding support for complex is rather easy, and eliminates the need to call float

class StrictInt(int):
 def __new__(cls, value, *args, **kwargs):
 # type: (Union[int, float, str], Any, Any) -> int
 
 if isinstance(value, (int, StrictInt)):
 return super(StrictInt, cls).__new__(cls, value)
 if isinstance(value, str):
 value = value.replace(' ', '')
 elif not isinstance(value, (float, complex)):
 type_str = str(type(value)).replace("<class '", "").replace("'>", "")
 raise TypeError("Cannot convert type '{type}' to strict integer".format(type=type_str))
 
 try:
 complex_value = complex(value)
 except ValueError:
 raise ValueError("Cannot convert a non-number to a strict integer.")
 if complex_value.imag:
 raise ValueError('Cannot convert complex number with imaginary part')
 
 float_value = complex_value.real
 if not float_value.is_integer():
 raise ValueError("Cannot convert value due to non-integer parts.")
 return super(StrictInt, cls).__new__(cls, int(float_value))

Python 2

If you want to include python 2, unicode should also be accepted as type

there are a fewcases that fail the current implementation that are integers

StrictInt(0)
StrictInt(3 + 0j)
StrictInt('3 + 0j')

fixing the first is as easy as changing if not f: to if f is None #Complex Since complex can not handle a string input, the easiest way to include this, is to use ast.literal_eval, and then if the type is complex, check whether value.imag is 0

naming

I try to avoid 1-letter variable names, unless it are x, y, z for coordinates, or i during an iteration, so I would rename f to float_value or something, but that is a matter of taste.

short_circuit

if value is an int or StrictInt already, you can return early. This way, you also

failing test-cases

there are a few cases that fail the current implementation that are integers

StrictInt(0)
StrictInt(0.0)
StrictInt(3 + 0j)
StrictInt('3 + 0j')

fixing the first is as easy as changing if not f: to if f is None

#Complex

adding support for complex is rather easy, and eliminates the need to call float

class StrictInt(int):
 def __new__(cls, value, *args, **kwargs):
 # type: (Union[int, float, str], Any, Any) -> int
 
 if isinstance(value, (int, StrictInt)):
 return super(StrictInt, cls).__new__(cls, value)
 if isinstance(value, str):
 value = value.replace(' ', '')
 elif not isinstance(value, (float, complex)):
 type_str = str(type(value)).replace("<class '", "").replace("'>", "")
 raise TypeError("Cannot convert type '{type}' to strict integer".format(type=type_str))
 
 try:
 complex_value = complex(value)
 except ValueError:
 raise ValueError("Cannot convert a non-number to a strict integer.")
 if complex_value.imag:
 raise ValueError('Cannot convert complex number with imaginary part')
 
 float_value = complex_value.real
 if not float_value.is_integer():
 raise ValueError("Cannot convert value due to non-integer parts.")
 return super(StrictInt, cls).__new__(cls, int(float_value))

Python 2

If you want to include python 2, unicode should also be accepted as type