I'd really like to hear from someone outside of academia who thinks this is useful. I've been programming in C-like languages ever since I graduated college 25 years ago, but my degree is in EE, not CS. The language definition is complete gibberish to me, containing solid pages of a mathematical notation that I've never before seen. Likewise, I have a very hard time following the demo code. I don't really feel qualified to evaluate it.
I do see some red flags, though. First, since the language spec is given in such an abstract notation I have a feeling that it's going to be very difficult for code monkeys like me to refer back to. I normally reach for the language spec or the official docs when I have a question, but neither are going to do me any good here. Similarly, the tutorial starts out by describing the similarities and differences between Ur and ML or Haskell. That'd be a lot more useful if I'd ever used either of those two languages. The tutorial is incomplete, and what's there never describes Ur on its own without comparing it to the other languages.
Second, the trivial demos look like some PHP variant, while the complicated demos are, well... Complicated. "Hello, World" simply returns a chunk of what appears to be free-form XML; some others return a chunk of XML with a few embedded Ur statements, similar to PHP. The SQL demos show embedded SQL statements. Are the XML and SQL chunks syntactically part of the Ur language thus checked for well-formedness, or are they just free-form text which get minimally processed to substitute variables before they're emitted? Or is there something else fundamental going on here that I'm missing completely due to my lack of familiarity with functional programming?
Third, the official web site looks like something out of 1995. That's not necessarily a bad thing. It is clean and functional, just really, really utilitarian. I assume the site is done in Ur/Web, and it's clear that the author of the language learned HTML back when Mosaic was the hot new browser. Is the utilitarian look just how the author or site designer does things, or is it baked into the language? How hard would it be to implement something that looks modern? In the same vein it looks like Ur/Web produces xhtml as its output, and it looks like Ur/Web pretty much relies on well-formed XML embedded in the Ur source code. Will it have access to any of the new goodies in HTML5? Or is it going to be obsolete before the first Dummies book can be written?
So if there's anyone here who does real-world web development and has the academic chops to evaluate Ur/Web for what it is, would you please post a summary for us code-troglodytes?