Using a Proc and nil?, i need to check if an array has a nil element or not in ruby-CodePudding

    def check_nill(array1)
      p = Proc.new {array1.any? { |x| x.nil? }}
      if p == true
        puts "true"  
      else  
        puts "false"  
      end 
     end

it always give me false and i dont know why

CodePudding user response：

Proc.new does not actually run the code. You have to pass it over, or call it using Proc#call.

is_nil = Proc.new {|item| item.nil?}
["a", "b", nil].any?(is_nil)
# => true

Your code always return false because p was an instance of Proc, and not the result of the block.

p = Proc.new {array1.any? { |x| x.nil? }} # <Proc:0x0000000>

if p == true # <Proc:0x0000000> == true? no
  puts "true"  
else
  puts "false" # prints false
end

CodePudding user response：

You are overdoing it, creating a proc inside a method and then not calling it.

  check_nil = proc {|ar| ar.any?{|x| x.nil?} # or just proc {|ar| ar.any?(nil)}

  puts check_nil.call([1,2,nil,3]) # => true