The type() function is mostly used for debugging purposes. Two different types of arguments can be passed to type() function, single and three arguments. If a single argument type(obj) is passed, it returns the type of the given object. If three arguments type(object, bases, dict) is passed, it returns a new type object.
Example:
In the given example, we are printing the type of variable x.
Python3
x = 10print(type(x)) |
Output :
<class 'int'>
Python type() function Syntax
Syntax: type(object, bases, dict)
Parameters :
- object: Required. If only one parameter is specified, the type() function returns the type of this object
- bases : tuple of classes from which the current class derives. Later corresponds to the __bases__ attribute.
- dict : a dictionary that holds the namespaces for the class. Later corresponds to the __dict__ attribute.
Return: returns a new type class or essentially a metaclass.
Examples of the type() function in Python
Finding the type of a Python object
Here we are checking the object type using the type() function in Python.
Python3
a = ("Geeks", "for", "Geeks")b = ["Geeks", "for", "Geeks"]c = {"Geeks": 1, "for":2, "Geeks":3}d = "Hello World"e = 10.23f = 11.22print(type(a))print(type(b))print(type(c))print(type(d))print(type(e))print(type(f)) |
Output:
<class 'tuple'> <class 'list'> <class 'dict'> <class 'str'> <class 'float'> <class 'float'>
Check if an Object is of Type in Python
In this example, we are testing the object using conditions, and printing the boolean.
Python3
print(type([]) is list)print(type([]) is not list)print(type(()) is tuple)print(type({}) is dict)print(type({}) is not list) |
Output :
True False True True True
Python type() With 3 Parameters
In the given example, we are creating a class without a base class and a class derived from a base class. The type() function allows for programmatically defining classes and their attributes at runtime.
Python3
# New class(has no base) class with the# dynamic class initialization of type()new = type('New', (object, ), dict(var1='Lazyroar', b=2009))# Print type() which returns class 'type'print(type(new))print(vars(new))# Base class, incorporated# in our new classclass test: a = "GeeksforLazyroar" b = 2009# Dynamically initialize Newer class# It will derive from the base class testnewer = type('Newer', (test, ), dict(a='Geeks', b=2018))print(type(newer))print(vars(newer)) |
Output :
<class ‘type’>
{‘var1’: ‘Lazyroar’, ‘b’: 2009, ‘__module__’: ‘__main__’, ‘__dict__’: <attribute ‘__dict__’ of ‘New’ objects>, ‘__weakref__’: <attribute ‘__weakref__’ of ‘New’ objects>, ‘__doc__’: None}
<class ‘type’>
{‘a’: ‘Geeks’, ‘b’: 2018, ‘__module__’: ‘__main__’, ‘__doc__’: None}
type() Function Applications
- type() function is basically used for debugging purposes. When using other string functions like .upper(), .lower(), and .split() with text extracted from a web crawler, it might not work because they might be of different type which doesn’t support string functions. And as a result, it will keep throwing errors, which are very difficult to debug [Consider the error as GeneratorType has no attribute lower() ].
- type() function can be used at that point to determine the type of text extracted and then change it to other forms of string before we use string functions or any other operations on it.
- type() with three arguments can be used to dynamically initialize classes or existing classes with attributes. It is also used to register database tables with SQL.
