Chunk
Problem statement
Implement a function chunk(array, [size=1]) that splits the input array into groups of length size and returns them within a new array.
If the array cannot be split evenly, the final chunk will contain the remaining elements. The function should not modify the original input array.
Example
chunk(['a', 'b', 'c', 'd'], 2); // => [['a', 'b'], ['c', 'd']]
chunk([1, 2, 3, 4], 3); // => [[1, 2, 3], [4]]How to approach Chunk
The strategy an interviewer expects you to reach for.
Chunking splits a list into fixed-size pages — think batching uploads or rendering windows. Naive move Nested loops that push one element at a time and forget the last partial chunk. Where it breaks Size < 1, non-arrays, and the remainder when length is not divisible by size. Mutating the source while slicing is unnecessary risk. The fix Guard bad input. Loop i += size and push(array.slice(i, i + size)). Slice naturally yields a shorter final chunk. Remember: slice(i, i+size) gives you the partial tail for free. Say this in the interview: I'd step by size and slice each window into a new array of chunks, including a shorter final page when needed.
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