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Errors & debugging

Handle failures gracefully, raise helpful errors, and debug with confidence.

6 matches

How to Handle ValueError and Multiple Exceptions in Python

This code demonstrates try/except blocks for beginners, handling ZeroDivisionError, TypeError, and ValueError with two practical functions: dividing numbers and parsing strings to floats.

try-except valueerror exception-handling

Python

def divide_numbers(a, b):
    """Divide two numbers with error handling for beginners."""
    try:
        result = a / b
        print(f"{a} / {b} = {result}")
        return result
    except ZeroDivisionError:
        print(f"Error: Cannot divide {a} by zero!")
    except TypeError:
        print(f"Error: Both argu…

14 0 Open

Errors & debugging easy

How to Inspect Local Variables in an except Block in Python

Capture and print local variables at the moment an exception occurs using locals() inside an except block.

debugging exception-handling locals

Python

def risky_operation(value):
    try:
        result = 10 / value
        return result
    except ZeroDivisionError as e:
        local_vars = dict(locals())
        print(f"Error: {e}")
        print("Local variables at exception:")
        for key, val in local_vars.items():
            print(f"  {key} = {val}")
   …

13 0 Open

Errors & debugging medium

How to attach a request ID to exception messages in Python

This code shows how to enrich exception messages with contextual request IDs using context variables, making error logs more traceable across concurrent requests.

contextvars exception-handling logging

Python

import logging
from contextvars import ContextVar

request_id_var = ContextVar("request_id", default="unknown")

def add_request_id(exc: Exception) -> Exception:
    exc.args = (f"request_id={request_id_var.get()} | {exc.args[0]}" if exc.args else f"request_id={request_id_var.get()}",) + exc.args[1:]
    return exc

d…

13 0 Open

Errors & debugging easy

How to handle ZeroDivisionError in Python

Wrap a division operation in try/except to return None or a friendly message instead of crashing when dividing by zero.

zero-division exception-handling try-except

Python

def safe_divide(a, b):
    """Return a/b if possible, else None when dividing by zero."""
    try:
        return a / b
    except ZeroDivisionError:
        return None


def safe_divide_with_message(a, b):
    """Return a how-to message on divide-by-zero error."""
    try:
        return a / b
    except ZeroDivisio…

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Errors & debugging easy

Implement a Context Manager That Suppresses Exceptions in Python

Shows how to write a custom context manager that catches specified exceptions and optionally re-raises others, plus the stdlib contextlib.suppress alternative.

context-manager exception-handling with-statement

Python

import contextlib

class SuppressExceptions:
    def __init__(self, *exceptions):
        self.exceptions = exceptions

    def __enter__(self):
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        if exc_type is None:
            return False
        if not self.exceptions or exc_type in se…

12 0 Open

Errors & debugging easy

Validate try except ValueError handler for beginners — errors debugging

Learn how to validate user input and handle division errors safely using try/except with ValueError and ZeroDivisionError in Python.

try except valueerror

Python

def divide_numbers(a, b):
    """Divide two numbers, catching division by zero and value errors."""
    try:
        result = a / b
    except ZeroDivisionError:
        print("Error: Cannot divide by zero!")
        return None
    except TypeError:
        print("Error: Both arguments must be numbers!")
        retu…

14 0 Open

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