Introspection

Ruby objects can report information about their classes and methods.

introspection.rb

class Calculator
  def add
    "add"
  end

  def subtract
    "subtract"
  end
end

prefix = 
methods = Calculator.public_instance_methods(false).map(&:to_s).sort
matches = methods.select { |method_name| method_name.start_with?(prefix) }
matches_text = matches.join("/")

puts "class=#{Calculator.name}"
puts "prefix=#{prefix}"
puts "matches=#{matches_text}"
puts "count=#{matches.length}"

class Calculator
  def add
    "add"
  end

  def subtract
    "subtract"
  end
end

prefix = 
methods = Calculator.public_instance_methods(false).map(&:to_s).sort
matches = methods.select { |method_name| method_name.start_with?(prefix) }
matches_text = matches.join("/")

puts "class=#{Calculator.name}"
puts "prefix=#{prefix}"
puts "matches=#{matches_text}"
puts "count=#{matches.length}"

class Calculator
  def add
    "add"
  end

  def subtract
    "subtract"
  end
end

prefix = 
methods = Calculator.public_instance_methods(false).map(&:to_s).sort
matches = methods.select { |method_name| method_name.start_with?(prefix) }
matches_text = matches.join("/")

puts "class=#{Calculator.name}"
puts "prefix=#{prefix}"
puts "matches=#{matches_text}"
puts "count=#{matches.length}"

introspection Introspection means asking code about its own shape, such as which methods a class defines.