Performing method call on object stored in array Ruby-CodePudding

I am trying to call the method details for object Person that is storred in array resut but keep getting this error undefined method 'details' for [#<Person:0x000001e277d58aa8 @name="Winston", @age=3>, #<Person:0x000001e277d58940 @name="Rob", @age=1>, #<Person:0x000001e277d58788 @name="Sam", @age=5>]:Array (NoMethodError)

This is the code that is throwing the error result.each { |p| p.details}. It is the last line of code. I am not sure why this is throwing an error and am even more confused becuase I made similar method calls earlier and they are not throwing errors.

class Person
  def initialize(name, age)
    @name = name
    @age = age
  end

  def details
    puts "Name: #{@name}\nAge: #{@age}"
  end

  def get_age
    return @age
  end
end

def generate_data(names)
  sample_pool = []

  names.each { |n| sample_pool << Person.new(n, rand(100)) }

  return sample_pool
end

def extract(sample_pool, criteria)
  result = []
  result << sample_pool.select { |n| n.get_age <= criteria}
  return result
end

names = ["Doug", "Matt", "Fred", "Fransisco", "Pete", "Rick", "Rob", "Tanner", "Greg", "Sherri", "Winston", "Sam", "Brett", "Georgia", "Alison", "Grant", "Brick", "Slick", "Van", "Fawn", "Sloan", "Harry", "Ron", "Jerry", "Jasmine", "Dawn", "Misty"].shuffle!

puts "Enter an age that you would like to search up too."
criteria = gets.chomp.to_i
sample_pool = generate_data(names)
result = extract(sample_pool, criteria)

result.each { |p| p.details}

CodePudding user response：

select returns an array, and << pushes the return value of select into result.

This means that result is a nested array. It looks like this:

[[Person<name: rob>, Person<name: Sam>, Person<name: Winston>]]

You want to create a flat array, so you could change extract to be something like this:

def extract(sample_pool, criteria)
  sample_pool.select { |n| n.get_age <= criteria}
end

CodePudding user response：

TonyArra answered your original question by modifying your extract method, but you mentioned in your comment, your generate_data method.

The use of the each method in generate_data adds a single Person for each name in your names Array, so you get what you expect, however a better way to implement that is to use map to "map" the String Array names into a Person Array

def generate_data(names)
    names.map {|n| Person.new(n, rand(100))}
end