What are Truthy and Falsy Values in Python, and How Are They Used?

Truthy and Falsy Values in Python

In Python, we encounter two distinct concepts: truthy and falsy values. These differ from the conventional True and False boolean values.

What are Truthy and Falsy Values?

Truthy values evaluate to True in conditional statements like if and while, even though they are not explicitly True. On the other hand, falsy values evaluate to False.

Falsy Values

Falsy values in Python include:

• None
• False
• The number 0, regardless of type (e.g., 0, 0.0, 0j)
• Empty sequences and collections (e.g., empty lists, dicts, tuples, sets, strings, bytes, bytearrays, memoryviews, zero-length ranges)

• Objects where:

  • obj.__bool__() returns False
  • obj.__len__() returns 0 (if bool is undefined)

Difference between Truthy and True, Falsy and False

• Truthy vs. True: Truthy values include True but also non-zero numbers, non-empty sequences, and objects for which bool returns True.
• Falsy vs. False: Falsy values include False but also explicitly specified falsy types like None and empty sequences.

When to Use Truthy and Falsy Values

Truthy and falsy values find applications in scenarios where an expression's truthiness is more important than its specific value. For instance, they can be used:

• To simplify conditional statements (e.g., if a value is truthy, it can be treated as a true condition)
• As default values in function parameters
• For input validation (e.g., checking if a value provided by the user is truthy)
• To check if a value is set (e.g., by assigning True or None to a variable depending on a condition)

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