[Solved] Identify the problem in this Ruby code:class User def initialize(name) @name = name end end user = User.new('Alice') user.instance_eval do def greet "Hello, #{@name}!" end end puts user.greet | Ruby

Ruby - Advanced Metaprogramming

Identify the problem in this Ruby code:

class User
  def initialize(name)
    @name = name
  end
end

user = User.new('Alice')
user.instance_eval do
  def greet
    "Hello, #{@name}!"
  end
end
puts user.greet

Auser.greet will raise NoMethodError

Bgreet method cannot access @name instance variable

Cinstance_eval block syntax is incorrect

Dgreet method is defined on singleton class, so user.greet works fine

Step-by-Step Solution

Solution:

Step 1: Understand instance_eval on object
The block defines method greet on the singleton class of user, so user.greet is valid.
Step 2: Check access to instance variables
Inside greet, @name is accessible because it's the same object.
Final Answer:
greet method is defined on singleton class, so user.greet works fine -> Option D
Quick Check:
instance_eval defines singleton methods = greet method is defined on singleton class, so user.greet works fine [OK]

Quick Trick: instance_eval defines singleton methods accessible on object [OK]

Common Mistakes:

Thinking instance variables inaccessible inside instance_eval method
Confusing block syntax
Expecting NoMethodError for greet

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Identify the problem in this Ruby code:

Step 1: Understand instance_eval on object

Step 2: Check access to instance variables

Final Answer:

Quick Check:

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