The below function will throw a NoMethodError when it is expected to calculate the sum of a given array.
By printing the result "p" it should return 10.
p [1,2,3,4].sum
#=> 10
Instead of getting the result of the sum, I get the error below.
undefined method `sum' for [1, 2, 3, 4]:Array (NoMethodError)
Check what version of ruby you're using with ruby -v
If you have a version older than 2.4, you can use inject instead.
[1, 2, 3, 4].inject(0,:+)
The above is a shorthand for
[1, 2, 3, 4].inject(0) {|sum, value| sum + value}
The zero 0 is needed to handle empty arrays, which otherwise would return nil