Try...Except Basics

Try...Except Basics

Errors happen. try/except catches them so your program can handle a problem instead of crashing.

The try block

Put risky code in try. The matching except catches any error:

try:
    print(x)
except:
    print("An exception occurred")

x isn't defined, so the try fails and the except block runs.

Catch a specific error

Name the exception type to handle only that one:

try:
    print(x)
except NameError:
    print("Variable x is not defined")
except:
    print("Something else went wrong")

Catch and inspect the error

try:
    print(x)
except NameError as e:
    print("Problem:", e)

Why it matters

Without try/except, an error stops the whole program. With it, you can react and keep going.

Common built-in exceptions

TL;DR

• try holds risky code; except handles errors.
• Name specific exceptions to catch only what you want.
• as e lets you inspect the error.
• Without it, errors crash your program.