Variable Naming Conventions

Choosing Descriptive Variable Names

This note covers best practices for choosing descriptive variable names in Python. The goal is to write code that is readable and maintainable.

Key Principles:

• Clarity over brevity: A slightly longer, descriptive name is far better than a short, cryptic one. For example, customer_total_price is superior to ctp.

• Reflect the data: The name should accurately reflect the type and purpose of the data stored in the variable. If a variable holds a list of user IDs, user_ids is a better choice than data or items.

• Consistency: Use a consistent naming style throughout your code. Python’s standard style guide (PEP 8) recommends snake_case (all lowercase with underscores separating words).

• Avoid reserved keywords: Don’t use Python keywords (e.g., if, else, for, while, class, def, etc.) as variable names.

• Meaningful prefixes/suffixes: In some cases, prefixes or suffixes can improve readability, especially when dealing with collections or specific data types. For example: user_count, product_list, is_active.

Examples:

Good:

customer_name = "Alice Smith"
order_total = 150.50
product_prices = [10.99, 25.00, 5.75
is_logged_in = True

Bad:

n = "Alice Smith"  # What does 'n' represent?
t = 150.50        # Too cryptic
p = [10.99, 25.00, 5.75 #What is p?
l = True         # What does 'l' mean?

Further Considerations:

• Data Types in Python - Understanding different data types helps choose appropriately descriptive names.
• Python Style Guide (PEP 8) - Provides detailed guidance on naming conventions and other style recommendations.
• Working with Lists in Python - Shows how descriptive names can improve readability when working with lists.