What Tom said, in both of his last two posts. Barr is saying nothing about whether it should be read figuratively or literally, only that the author uses "yom" in the 24-hour sense. I agree with this entirely. I think the author was using "yom" in the 24-hour sense. The way a poet would be using "tree" in the natural, branch and leaf, sense even when using that "tree" to refer to a family.
The structure and style of both of the Genesis creation accounts, while different, are both very much in the neareastern literary tradition. They have the same epic/mythic language and structure that we see in Sumerian, Hittite and Egyptian literature (not to mention many of the exact same details throughout Genesis). We know that these cultures did not view these stories of their past as literal history, although they considered them "true" accounts of their past. We, with our modern, empirical minds, really struggle with this concept because we associate historicity with "true" accounts of the past. In ancient times, they had no idea of being able, or even wanting, to tell about such things with historical accuracy. They passed down the stories that conveyed what they believed truly reflected the nature of their past, of origins, etc, in more general and evocative terms. This is shown by the fact that they often had two overlapping and conflicting accounts they told simultaneously. They both could not historically accurate, since they contradict each other in some obvious points, but they told them both side by side and believed them both. To them, they were both "true" in a sense we just don't "get" today.
Not surprisingly, we have the same thing happening in Genesis, two overlapping and, in a number of areas, conflicting, accounts. Yet, they told them side by side, and even wrote them down later side by side. An immense amount of work has been done in modern times to make these two accounts coincide, a huge effort that would puzzle the ancient writers and readers entirely.