I think reading through all the examples https://github.com/seanbaxter/circle/blob/master/examples/RE... makes it clear that the author has put quite a deal of thought into how these features make it easier to write clear, understandable and maintainable code.

Even the example you point to goes to say: "Let's use the integrated interpreter to define a useful build tool. Software is the subject of constant revisions, and it's useful to mark a distributable with the exact version of the source-control archive it was built with." It's clear (to me) that the developer is not advocating using terminal input in the middle of a build. I haven't used terminal input since I was a child; I don't think the developer expects anyone to take that as a serious example.