# =========================================
# ringbuf.rb
#
# Ringbuffer Class.
# =========================================

class RingBuffer

    # Instanciate a ring buffer of the given size.
    # The buffer will contain at most +size+ elements
    def initialize(size)
        @max = size
	@buffer = []
    end

    # Add an element at the end of the buffer
    # If size is exceeded, the first element is dropped
    def push(line)
        @buffer.push(line)
	if @buffer.size > @max
	    @buffer.shift
	end
    end

    # Resets buffer
    def clear 
        @buffer=[]
    end

    # Return the content as Array
    def to_a
        return @buffer.dup
    end

    # Return content as a string containing each entry
    # on a single line
    def to_s
	str = ""
        @buffer.each { |entry|
	    str << entry << "\n"
	}
        return str  
    end

    # Call the closure block on each element in the buffer
    def each(&block)
        @buffer.each(&block)
    end
end