class Array

Calculate the longest common prefix for all elements in the array.

Requires array elements to support size and take operations

@api public @return [Object] The largest common prefix for all elements in the array @example [['a', 'b'], ['a', 'b', 'c', 'd'], ['a', 'b', 'e', 'f']].prefix # => ['a', 'b']

# File lib/snmputils/arrayutils.rb, line 22
def prefix
  pairwise_prefix = lambda do |short, long|
    if short.size == 0 or long .size == 0
      short.class.new
    else
      if short.size > long.size
        pairwise_prefix.call(long, short)
      elsif short == long.take(short.size)
        short
      else
        pairwise_prefix.call(short.take(short.size - 1), long)
      end
    end
  end
  reduce &pairwise_prefix
end

Convenience method to return the second element in the list

@api public @return [Object] The second object in the array @example ['a', 'b', 'c'].second # => 'b'

# File lib/snmputils/arrayutils.rb, line 11
def second
  return at(1)
end

Calculate the longest common suffix for all elements in the array.

Requires array elements to support size and take operations

@api public @return [Object] The largest common suffix for all elements in the array @example [['y', 'z'], ['w', 'x', 'y', 'z'], ['u', 'v', 'y', 'z']].suffix # => ['y', 'z']

# File lib/snmputils/arrayutils.rb, line 46
def suffix 
  prefix = (map { |x| x != nil && x.reverse }).prefix
  prefix.reverse if prefix
end