Recently, I've invested time looking at current compiling-to-JavaScript developments. Although people have been doing this for many years now, it seems CoffeeScript is making it clear that being a target of compilation is at least part of JavaScript's future. The pending additions in browsers of support for debugging original source language seems to reinforce this future direction as a serious possibility.
JavaScript doesn't have macros to allow programmers to tune the language to their likes and needs. So it seems that developers have decided that compiling to JavaScript is the route to go because they can do that right now. They are, however, limited by the features that are part of JavaScript with regard to what features the source language can have that are efficient in the compiled JavaScript. Additions to JavaScript, especially low-level functionality, will open doors for the source languages. The most interesting part of the block lambda proposal is adding lambdas to JavaScript. Regardless of syntax, this would mean a lot of possibilities open for languages targeting JavaScript. Often a heavy function is not a good idea in the compiled code and the lack of Tennent's Correspondence Principle for functions means the compilers need to do big tricks to get the compiled code to do what is desired. As a trivial example, if JavaScript had lambdas but no let blocks then a source language could add efficient let blocks quite easily. What is the current feeling about the block lambda proposal in TC39? What can be done to help move the block lambda proposal towards Harmony? Peter _______________________________________________ es-discuss mailing list es-discuss@mozilla.org https://mail.mozilla.org/listinfo/es-discuss
