Track 9 · Lesson 8 of 11

EAFP versus LBYL

Compare 'easier to ask forgiveness than permission' with 'look before you leap', and choose between try, an if check and dict.get for each situation.

You will be able to

• Describe the EAFP and LBYL styles and recognise each in code
• Choose between dict.get, an in check and try/except KeyError for a lookup
• Explain why checks like isdigit() are a poor substitute for trying a conversion
• Use EAFP to reach into nested data without a chain of checks