Python Debugging: Why Print Statements Still Beat Your Fancy IDE

 

Python Debugging: Why Print Statements Still Beat Your Fancy IDE

Aaron Rose

Aaron Rose       
Software Engineer & Technology Writer


Your IDE promised you the world. Breakpoints, variable inspection, call stacks that look like NASA mission control. But here's the truth: when your code breaks at 2 AM and the client is breathing down your neck, you're going to reach for print().

And you know what? You should.

The Debugger Lie

Modern IDEs sell us a beautiful story. Set a breakpoint, step through line by line, hover over variables to see their values. It's supposed to be surgical, precise, professional.

But real debugging isn't a controlled lab experiment. It's messy, urgent, and often happening in environments where your fancy debugger can't even connect.

# What the tutorials show you
def calculate_total(items):
    total = 0  # <- Set breakpoint here, inspect variables
    for item in items:
        total += item.price
    return total
# What actually happens in production
def calculate_total(items):
    print(f"DEBUG: Starting with {len(items)} items")
    total = 0
    for i, item in enumerate(items):
        print(f"DEBUG: Item {i}: {item.price} (running total: {total})")
        total += item.price
        if total < 0:  # This shouldn't happen...
            print(f"ALERT: Negative total detected! Item was: {item}")
    print(f"DEBUG: Final total: {total}")
    return total

Guess which one actually helps you find the bug?

When Debuggers Fail You

Remote Servers Don't Care About Your IDE

Your Django app works fine locally. In production? It's throwing 500s. Your debugger can't connect to the remote server, but print() statements show up in the logs every time.

# This works everywhere, every time
def process_payment(amount, user_id):
    print(f"Processing payment: ${amount} for user {user_id}")

    if not user_id:
        print("ERROR: No user_id provided!")
        raise ValueError("User ID required")

    # More debugging breadcrumbs...

Docker Containers Are Print Statement Territory

Ever tried debugging inside a Docker container? Good luck attaching your IDE's debugger to that. But print statements? They show up in docker logs like faithful soldiers.

The Async/Threading Nightmare

Debugging async code or multithreaded applications with traditional debuggers is like trying to catch smoke with your hands. Print statements with timestamps, though? They tell the story exactly as it unfolded.

import asyncio
from datetime import datetime

async def fetch_data(url):
    timestamp = datetime.now().strftime("%H:%M:%S.%f")
    print(f"[{timestamp}] Starting fetch for {url}")

    # Your async code here

    print(f"[{timestamp}] Completed fetch for {url}")

The Print Statement Advantages

1. They're Always There

Your debugger might crash. Your IDE might freeze. VS Code might decide today's the day it doesn't feel like connecting. But print() never lets you down.

2. They Show the Flow

Debuggers show you one moment in time. Print statements show you the entire story - the sequence of events that led to the problem.

def mysterious_bug(data):
    print("=== Starting mysterious_bug ===")

    for item in data:
        print(f"Processing item: {item}")
        result = transform(item)
        print(f"Transform result: {result}")

        if validate(result):
            print(f"Validation passed for {result}")
        else:
            print(f"VALIDATION FAILED for {result}")
            # Now you know exactly where it breaks

3. They're Permanent (Until You Remove Them)

Set a breakpoint, restart your app, and oops - breakpoint's gone. Print statements stick around through restarts, deployments, and that time you accidentally closed your IDE.

4. They Work in Any Environment

Production server? Print works. Lambda function? Print works. Raspberry Pi running in your garage? Print definitely works.

The Right Way to Print Debug

Don't just throw print("here") everywhere like confetti. Be strategic:

Use Descriptive Messages

# Bad
print(user)

# Good  
print(f"User object before validation: {user}")

Add Context

# Bad
print(total)

# Good
print(f"Cart total after applying discount {discount_code}: ${total}")

Use Timestamps for Race Conditions

import time

def debug_timing_issue():
    print(f"[{time.time()}] Function started")
    # your code
    print(f"[{time.time()}] Function finished")

The Hybrid Approach

Here's the secret: the best developers use both. Use your debugger for stepping through complex logic. Use print statements for everything else - especially the stuff that happens over time, across requests, or in environments where debuggers fear to tread.

def smart_debugging_example(complex_data):
    # Debugger territory: complex transformations
    processed = transform_complex_data(complex_data)

    # Print statement territory: what actually happened
    print(f"Processed {len(complex_data)} items into {len(processed)} results")

    return processed

The Bottom Line

Your IDE's debugger is a beautiful, sophisticated tool. But when the chips are down and you need to figure out why your code is misbehaving in the wild, print() is your most reliable friend.

It's not glamorous. It's not what the coding bootcamps teach. But it works, everywhere, every time.

Sometimes the old ways are the best ways.

Now excuse me while I go remove 47 print statements from my production code...


Aaron Rose is a software engineer and technology writer at tech-reader.blog and the author of The Rose Theory series on math and physics.

Comments

Popular posts from this blog

The New ChatGPT Reason Feature: What It Is and Why You Should Use It

Raspberry Pi Connect vs. RealVNC: A Comprehensive Comparison

Running AI Models on Raspberry Pi 5 (8GB RAM): What Works and What Doesn't