How to deal with nil?

[LouisDeconinck]

In my data, I have a table called 'Effect2'. This lists a secondary effect some cards have, which is displayed through an image. However, not every card has such a secondary effect. As such this secondary effect parameter has the following contents: ['power', 'spread', nil, nil, 'vision', 'power', nil, 'power', nil, nil, ...]

The intended use is that an image is displayed corresponding to the power, if such a secondary power if nothing exists nothing needs to be displayed.

In order to display this secondary effect I have the following code:

  data['Effect2'].map do |e|
    unless data['Effect2'].nil?
      png file: data['Effect2'].map { |t| "images/#{t.to_s.downcase}.png"}, x: 320, y: 800, width: :scale , height: 150
    end
  end

While this does work as intended, it throws a bunch of errors. I get the following message every time nil is in the 'Effect2' data.
[WARN] File/images/.png does not exist!

How can I get rid of this warning or is there a better way on how to handle this?

[LouisDeconinck]

The issue with my code is that I check the entire array for nil, instead of checking each item in the array. I should have checked if e is nil instead of data['Effect2'].

The following code does work and is cleaner:

png file: data['Effect2'].map { |t| t.nil? ? nil : "images/#{t.to_s.downcase}.png"}, x: 305, y: 800, width: :scale , height: 150