Short-circuiting in conditions in Blockchain / Solidity - Mini Project: Build & Apply

Short-circuiting in conditions

📖 Scenario: You are building a simple blockchain transaction validator. Each transaction has a sender balance and a requested amount to send. You want to check if the transaction is valid by ensuring the sender has enough balance and the amount is positive.

🎯 Goal: Learn how to use short-circuiting in conditions to efficiently check multiple requirements in one statement.

📋 What You'll Learn

Create a dictionary called transaction with keys 'balance' and 'amount' with exact values 100 and 50

Create a variable called is_valid that uses a short-circuiting and condition to check if transaction['balance'] is greater than or equal to transaction['amount'] and transaction['amount'] is greater than 0

Print the value of is_valid

💡 Why This Matters

🌍 Real World

Short-circuiting conditions help blockchain developers quickly validate transactions without unnecessary checks, improving performance and security.

💼 Career

Understanding short-circuiting is important for writing efficient smart contracts and blockchain validation logic.

1

Create the transaction data

Create a dictionary called transaction with these exact entries: 'balance': 100 and 'amount': 50.

Blockchain / Solidity

# Create the transaction dictionary with balance and amount
# Your code here

Need a hint?

Use curly braces to create a dictionary with keys 'balance' and 'amount'.

2

Set up the validation variable

Create a variable called is_valid and set it to False as a starting point.

Blockchain / Solidity

transaction = {'balance': 100, 'amount': 50}
# Create a variable is_valid and set it to False
# Your code here

Need a hint?

Just assign False to is_valid for now.

3

Use short-circuiting to check conditions

Update the variable is_valid to use a short-circuiting and condition that checks if transaction['balance'] >= transaction['amount'] and transaction['amount'] > 0.

Blockchain / Solidity

transaction = {'balance': 100, 'amount': 50}
is_valid = False
# Update is_valid to check if balance is enough and amount is positive using 'and'
# Your code here

Need a hint?

Use the and operator to combine both conditions in one line.

4

Print the validation result

Write a print statement to display the value of is_valid.

Blockchain / Solidity

transaction = {'balance': 100, 'amount': 50}
is_valid = transaction['balance'] >= transaction['amount'] and transaction['amount'] > 0
# Print the value of is_valid
# Your code here

Need a hint?

Use print(is_valid) to show the result.