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local_variables 

        # Binding.local_variables

(from ruby core)
---
    binding.local_variables -> Array

---

Returns the names of the binding's local variables as symbols.

    def foo
      a = 1
      2.times do |n|
        binding.local_variables #=> [:a, :n]
      end
    end

This method is the short version of the following code:

    binding.eval("local_variables")

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