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Ruby undefined method while using PriorityQueue

I'm trying to use a priorityQueue from https://github.com/ldonnet/priority_queue on ruby, after installing it with gem install priority_queue, i'm having the error :

./example.rb:5:in `<main>': undefined method `push' for #<PriorityQueue:0x000000015ca200 @queues={}> (NoMethodError)

When trying to run an example of the README.md file :

#!/usr/bin/ruby
require 'priority_queue'

q = PriorityQueue.new
q.push "node1", 0 
q.push "node2", 1

q.min #=> "node1"

q.decrease_priority("node2", -1)

q.pop_min #=> "node2"
q.min     #=> "node1"

ruby version : ruby 1.9.3p484 (2013-11-22 revision 43786) [x86_64-linux]

Thank you

Solution

  • The gem you linked do is (a fork of) the PriorityQueue gem, not the priority_queue gem. You need gem install PriorityQueue.

    I realize that the repository you linked to says gem install priority_queue in the readme, but, that does not appear to be correct. The priority_queue gem is from a different repository.