CODEWITHSUNDEEP
ruby-on-railsrubyruby-on-rails-3.2
BBQ Chef
BBQ Chef

Reputation: 696

Ruby exits my each loop when an if-statement inside is false

Why does code below exit the each loop as soon as the if-statement "g2k.has_key?(k)" is false

  e.element_children.all? do |n|
    k = n.name.to_sym
    logger.info("#{n.name} as symbol is '#{k}' is valid? = #{g2k.has_key?(k)}")
    if g2k.has_key?(k)
      logger.info("#{g2k[k] }= #{n.content}")
    #  @vehicle_data[g2k[k]] = n.content
    end
  end

This loops through all element children as intended

  e.element_children.all? do |n|
    k = n.name.to_sym
    logger.info("#{n.name} as symbol is '#{k}' is valid? = #{g2k.has_key?(k)}")
    #if g2k.has_key?(k)
    #  logger.info("#{g2k[k] }= #{n.content}")
    #  @vehicle_data[g2k[k]] = n.content
    #end
  end

I'm using rails 3.2 with Ruy 1.9, parsing XML with nokogiri.

Upvotes: 0

Views: 523

Answers (2)

weexpectedTHIS
weexpectedTHIS

Reputation: 3376

Unless you are capturing the output of the .all? method you should not be using it. .all? is used to make sure every element in an array returns true. .each will just iterate over all of them. .detect will iterate until true is returned.

Upvotes: 0

Jesse Wolgamott
Jesse Wolgamott

Reputation: 40277

Once all? finds something false, then it can't be all, so it's going to stop processing.

Here's an example: http://rubyfiddle.com/riddles/cb777 --- you'll see that it stops after printing 5 because 5 is not < 5

(1..20).all? do |i|
  puts i
  i < 5
end

# prints:
1 
2 
3 
4 
5

Upvotes: 3

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