reduce.rb

def reduce(coll, initial = nil, sym = nil, &blk)
  if block_given? && sym.nil?
    reduce_with_block coll, initial, &blk
  else
    reduce_without_block coll, initial, sym
  end
end

def reduce_with_block(coll, initial, &blk)
  memo = initial || coll.first
  skipped = false
  coll.each do |e|
    if !initial && !skipped
      skipped = true
      next
    end
    memo = blk.call memo, e
  end
  memo
end

def reduce_without_block(coll, initial, sym)
  if sym.nil?
    sym, initial = initial, nil
  end
  reduce_with_block(coll, initial) {|memo, obj| memo.send(sym, obj) }
end

dear tabs... wtf