


Exceptions Handling: , vs. as in except Statements
Python provides two methods to handle exceptions within try...except blocks: using a comma (,) or the as keyword. This article explores the differences between these two approaches, including their legality and compatibility across Python versions.
Comma (,) Syntax
The comma syntax is the traditional method of exception handling in Python. It allows you to specify multiple exception types to catch, as shown in this example:
<code class="python">try: pass except Exception, exception: pass</code>
In this code, the except statement declares two arguments separated by a comma. The first argument, Exception, specifies the general exception class to catch. The second argument, exception, is a variable that stores the specific exception object that was raised.
as Syntax
The as syntax was introduced in Python 2.6 as a more precise and Python 3-compatible way to handle exceptions. It involves using the as keyword to assign the specific exception object to a variable, as seen here:
<code class="python">try: pass except Exception as exception: pass</code>
In this example, the except statement assigns the specific exception object to the exception variable using the as keyword. This approach is unambiguous and eliminates the need for a second argument to catch the exception.
Validity and Compatibility
The as syntax was introduced in Python 2.6 but is not supported in Python 2.5 or earlier. The comma syntax, however, is valid in all versions of Python.
For clarity and forward compatibility, it is recommended to use the as syntax in Python 2.6 and later. In Python 2.5 and earlier, the comma syntax remains the only available option.
The above is the detailed content of Here are a few question-based titles that fit your article: * Python Exception Handling: Comma (,) or `as` in `except` Statements? * Which is Better: Using Comma (,) or `as` in Python\'s `except` S. For more information, please follow other related articles on the PHP Chinese website!

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