As The Register explains, this JavaScript engine isn’t aimed at use but rather to make the process of researching the future of the language more inclusive. From Mozilla Labs Tom Austin:
“In programming language (PL) research, we like to write up fancy evaluation rules containing lots of Greek letters. Unfortunately, these rules tend to be inscrutable to anyone who isn’t a PL researcher. Even for PL researchers, there is something unsatisfying about seeing a bunch of rules on a piece of paper.”
Practical concerns rank on his list along side syntax and semantics. JavaScript, especially as implemented in browsers, is the target of a lot of programmers’ ire. Perhaps this effort will lead to more of those who complain the loudest contributing ideas and code. I believe self interest is a powerful motivator so it’s more than likely going to be a benefit of the Narcissus engine and its companion script look-up tool, Zaphod.
Mozilla Labs pops out JavaScript language tool for coders, The Register