Canonical Way to Check for Type in Python

A tuple in Python is an ordered collection of items that cannot be changed once, making it immutable. This allows duplicate values and can hold elements of different data types, such as strings, numbers, other tuples, and more. This makes tuples useful for grouping related data while determining the content remains fixed and unchanged.

What is Canonical Way?

In programming, "canonical" refers to the standard, widely accepted, or recommended way approach to accomplishing a task. It determines with best practices and this is favored by the community or official documentation. In Python, performing a task canonically means using the most proper or Pythonic method.

Canonical Way to Check for Type in Python

In Python, the canonical definition of a tuple is an immutable, or ordered collection of items, usually mixed data types that are defined by comma-separated values in parentheses.

• Using instance() Method

• Using isinstance() Method

Here, we define a my_tuple as a tuple containing three elements: an integer, a string, and a floating-point number. The print statement gives the entire tuple and displays the original order.

my_tuple = (1, "helloworld", 3.14)
print(my_tuple)

The result is obtained as follows -

(1, 'helloworld', 3.14)

Using instance() Method

We need to determine whether an object (say x) is an instance of a specified type. We can use the type() function to obtain its type and check its statement.

Example

The following example defines x as the string "Hello". This checks that x is exactly. of type str using type(x) is str. Since this condition is true, it prints "x is an instance of str." -

x = "Hello"
if type(x) is str:
   print("x is an instance of str")

This will give the output as -

x is an instance of str

Using isinstance() Method

The isinstance() function is considered canonical because it effectively works with subclasses, which allows for flexible type checking. It supports multiple types, determined by different class structures. This also enables checking against multiple types at once.

Example

We need to check if x is an instance of Myclass or any of its subclasses. We can use the isinstance() method.

This Python code defines x as the string "Hello". It checks if x is an instance of the str class or any of its subclasses using isinstances(x, str). Since the condition is true, "x is an instance of str".

x = "Hello"
if isinstance(x, str):
   print("x is an instance of str")

We will give the output as -

x is an instance of str