[Solved] Find the bug in this Ruby code using functional style inside an OOP class: class Multiplier def initialize(factor) @factor = factor end def multiply(numbers) numbers.... | Ruby

Ruby - Functional Patterns in Ruby

Find the bug in this Ruby code using functional style inside an OOP class:

class Multiplier
  def initialize(factor)
    @factor = factor
  end

  def multiply(numbers)
    numbers.map { |n| n * factor }
  end
end

m = Multiplier.new(3)
puts m.multiply([1, 2, 3]).inspect

Amap method cannot be used on arrays.

Bfactor should be @factor inside the block.

Cmultiply method should return a string.

Dinitialize method is missing a return statement.

Step-by-Step Solution

Solution:

Step 1: Identify variable usage inside block
Inside the block, 'factor' is undefined; instance variable @factor should be used.
Step 2: Understand Ruby instance variable scope
Instance variables require @ prefix to be accessed inside blocks or methods.
Final Answer:
factor should be @factor inside the block. -> Option B
Quick Check:
Use @factor to access instance variable inside blocks [OK]

Quick Trick: Use @ for instance variables inside blocks [OK]

Common Mistakes:

Using local variable names instead of instance variables
Thinking map cannot be called on arrays
Expecting initialize to return a value

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Find the bug in this Ruby code using functional style inside an OOP class:

Step 1: Identify variable usage inside block

Step 2: Understand Ruby instance variable scope

Final Answer:

Quick Check:

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