[Solved] Identify the error in this Ruby code snippet: arr = [1, 2, 3, 4] result = arr.flat_map { |x| x * 2 } puts result.inspect | Ruby

Ruby - Enumerable and Collection Processing

Identify the error in this Ruby code snippet:

arr = [1, 2, 3, 4]
result = arr.flat_map { |x| x * 2 }
puts result.inspect

Aflat_map cannot be called on nested arrays.

BThe variable 'result' is not assigned properly.

CThe syntax of the block is incorrect.

Dflat_map block returns integers, not arrays, so flattening fails.

Step-by-Step Solution

Solution:

Step 1: Analyze block return values
The block { |x| x * 2 } returns integers, not arrays or enumerables.
Step 2: Understand flat_map flattening requirement
flat_map expects the block to return arrays or enumerables to flatten one level; returning integers causes flattening to fail or unexpected results.
Final Answer:
flat_map block returns integers, not arrays, so flattening fails. -> Option D
Quick Check:
Block must return arrays for flat_map flattening [OK]

Quick Trick: Block must return arrays, not single values, for flat_map [OK]

Common Mistakes:

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