Anonymous and Arrow Functions + JS Objects vs Python Dictionaries + Arrays vs Python Lists + Error Handling + Debugging

Anonymous and arrow functions

• short syntax

• common in callbacks and event handlers

JS objects vs python dictionaries key differences

• Prototype chain exists

• Property access via dot or bucket

• Prototype pollution is a real attack

arrays vs python lists

• Dynamic size

• Mixed types allowed

• Many functional helpers (map, filter)

• Security note: misuse of arrays often leads to logic errors

error handling differences from Python

• No checked exceptions

• Errors are often accidentally ignored

essential tools for debugging:

• console.log()

• console.error()

• DevTools breakpoints

• Inspect variables live

security angle for debugging

• attackers use DevTools too

• Never hide secrets in JavaScript