Find if an array of objects includes an attribute with a specific value

Question

The following code works, but can you tell me if this is the right way to do it?

I have an array of Position objects and I want to check if it contains an object which attribute 'hidden' has "false' value:

<% if positions.collect{|position| position.hidden}.include?(false) %>
  ...
<% end %>

If you like, another way to simplify this is: if positions.map(&:hidden).include?(false). (Warning: this and the original approach will behave differently from the answers given below if the 'hidden' attribute ever returns nil.) — antinome
– antinome, Commented Mar 20, 2013 at 16:04

Mike Lewis · Accepted Answer · 2011-03-19 05:47:27Z

34

<% if positions.any?{|position| !position.hidden} %>
  ...
<% end %>

Using the any? method

answered Mar 19, 2011 at 5:47

Mike Lewis

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Comments

Jacob · Accepted Answer · 2011-03-19 05:48:04Z

5

if positions.any? {|position| not position.hidden}

answered Mar 19, 2011 at 5:48

Jacob

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Tamik Soziev · Accepted Answer · 2012-04-14 00:48:57Z

1

you can also use all? method:

<% unless positions.all? {|position| position.hidden} %>
 ...
<% end %>

answered Apr 14, 2012 at 0:48

Tamik Soziev

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