module Enumerable

Converts enum to a Hash.

Each element of enum must be a single item, or an array of two items. Duplicate keys are overwritten in order.

[].to_h             #=> {}
[1,2].to_h          #=> {1=>nil, 2=>nil}
(1..2).to_h         #=> {1=>nil, 2=>nil}
[[1,2],[3,4]].to_h  #=> {1=>2, 3=>4}
[[1,2],[1,4]].to_h  #=> {1=>4}

# File lib/enum_to_h.rb, line 14
def to_h
        hsh = {}
        each do |k,v,*x|
                raise ArgumentError, "invalid number of elements (#{x.length+2} for 1..2)" if x.any?
                hsh[k] = v
        end
        hsh
end