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Discover how to streamline your Python code when dealing with multiple if statements by utilizing dictionaries and assignment expressions.
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Simplifying Conditional Statements in Python: Using Dictionaries and Assignment Expressions

In Python programming, we often find ourselves faced with the challenge of managing multiple conditional statements. If you've ever written a series of if-elif statements, you might have noticed how repetitive and lengthy they can get. This post addresses a common scenario: how to simplify your code when you want to perform the same task based on multiple conditions.

The Problem

Consider the scenario where you have a variable number that can take various values, and based on that value, you want to assign a word representation (word_form) and determine if the program should continue running (continue_program). Here's a simple example of what the code might look like:

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While this code is functional, it involves repeated assignments of continue_program = "Yes", which can be simplified.

The Solution

To streamline this process, we can leverage Python's dictionary data structure. Instead of multiple if-elif checks, we can map our numbers to their string representations in a dictionary. This approach dramatically reduces redundancy and improves code clarity.

Step-by-Step Simplification

Create a Dictionary:
Start by creating a dictionary where the keys are the numbers (1, 2, 3) and the values are their corresponding string representations ("one", "two", "three").

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Use an Assignment Expression (Python 3.8+ ):
With the use of the := operator (also known as the walrus operator), you can assign and evaluate in a single expression. This allows us to check if the number exists in the dictionary and assign its corresponding string to word_form.

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In this line:

d.get(number, "") fetches the word associated with number, or returns an empty string if the number isn’t found.

The value assigned to word_form will determine the boolean outcome of continue_program.

Examples

Here’s how the functionality works with different number values:

When number == 6:

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When number == 1:

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Pre-Python 3.8 Alternative

If you're using a version prior to Python 3.8, you can achieve similar functionality without the walrus operator:

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Conclusion

By using a dictionary and an assignment expression, you can considerably reduce repetitive code and make your decisions more efficient and readable. No longer do you need to repeat the same assignment statement for each condition; this streamlined approach enhances not only the functionality but also the maintainability of your code.

Now, you have a safer and cleaner way of managing your conditional statements in Python. Happy coding!