7 Tips For Handling Python Exception

Introduction

Photo by Pedro Lastra on Unsplash

Exception handling is commonly seen in Java, C++ or any other modern programming languages. Similarly, in Python, it has two types of errors — syntax errors and exceptions. Syntax errors refer to the syntactic problems which are detected by interpreter when translating the source code into byte code, while the exceptions are only detected during the runtime when the particular line is evaluated and executed. Python exceptions can be handled by application code but not the syntax errors.

In this article, we will discuss about the different ways to handle Python exceptions and when shall we use them.

Raise Exception

Python has a list of built-in exceptions which can be generated by interpreter or the built-in functions. Before we touch on the exception handling, let’s first look at how to raise a built-in exception.

Without implementing any new exception, you can use the raise keyword to throw out a built-in exception from your code. For instance, the below code checks the data type and value for mode variable, and raises built-in exceptions when wrong data type or value specified:

if not isinstance(mode, int):
    raise TypeError("mode must be numeric values") 
if not mode in [0, 1]: 
    raise…