[Solved] Find the error in this Ruby code snippet:arr = [1, nil, 2] new_arr = arr.compact! puts new_arr — Ans: compact! returns nil if no changes, so puts may print nothing | Ruby

Ruby - Arrays

Find the error in this Ruby code snippet:

arr = [1, nil, 2]
new_arr = arr.compact!
puts new_arr

ANo error; code works correctly

Bcompact! returns nil if no changes, so puts may print nothing

Ccompact! is not a valid method

Darr.compact! modifies arr but does not return new_arr

Step-by-Step Solution

Solution:

Step 1: Understand compact! return value
compact! returns nil if no nil values were removed, otherwise returns the modified array.
Step 2: Check if any nils removed
Since arr contains one nil, compact! removes it and returns the modified array, so new_arr is the array without nil.
Step 3: Consider edge case
If arr had no nils, compact! would return nil, and puts new_arr would print nothing, which can be confusing.
Final Answer:
compact! returns nil if no changes, so puts may print nothing -> Option B
Quick Check:
compact! may return nil = B [OK]

Quick Trick: compact! returns nil if no nil removed [OK]

Common Mistakes:

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