Method_added hook in Ruby - Time & Space Complexity

Time Complexity: Method_added hook

O(n)

Understanding Time Complexity

We want to understand how the time it takes to run code changes when using the method_added hook in Ruby.

Specifically, we ask: how does adding methods affect the work done by this hook?

Scenario Under Consideration

Analyze the time complexity of the following code snippet.

class MyClass
  def self.method_added(name)
    puts "Method added: #{name}"
  end

  def foo
    # some code
  end

  def bar
    # some code
  end
end

This code prints a message every time a new method is added to the class.

Identify Repeating Operations

Identify the loops, recursion, array traversals that repeat.

• Primary operation: The method_added hook runs once for each method defined.
• How many times: It runs exactly as many times as methods are added to the class.

How Execution Grows With Input

Each time you add a method, the hook runs once, doing a simple print.

Input Size (n)	Approx. Operations
10	10 print operations
100	100 print operations
1000	1000 print operations

Pattern observation: The work grows directly with the number of methods added.

Final Time Complexity

Time Complexity: O(n)

This means the time grows in a straight line with the number of methods added.

Common Mistake

[X] Wrong: "The method_added hook runs only once no matter how many methods are added."

[OK] Correct: The hook runs every time a new method is defined, so it runs as many times as methods are added.

Interview Connect

Understanding how hooks like method_added work helps you reason about code that reacts to changes, a useful skill in many Ruby projects.

Self-Check

"What if the method_added hook itself defined another method? How would that affect the time complexity?"