The First Class Function
A medium Python mock interview question on DataDriven, with an AI interviewer who asks follow-up questions and a hire or no-hire decision at the end.
- Domain
- Python
- Difficulty
- medium
- Seniority
- L4
Interview Prompt
We process a stream of transform requests, each naming one of a few registered integer transforms (`double`, `inc`, `square`) and carrying an integer `x`. An `apply_twice` request runs its named transform on `x` twice; a `compose` request pulls two named transforms and feeds `x` through both. Return one result per request, in the order they arrive.
Summary
Functions travel as values - prove you can pass one around.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write and run your Python against test cases
- Answer the interviewer's follow-up questions, then get a hire or no-hire decision