On Thu, Aug 21, 2008 at 6:31 AM, Brendan Eich <[EMAIL PROTECTED]> wrote:
> More helpful would be > comments on the utility of let blocks (a.k.a. let statements) and let > expressions. Also comparisons to the several let forms in Scheme (Jon > Z. posted something a while ago on this topic). I was reading the resulting ticket a few days ago. http://bugs.ecmascript.org/ticket/375 I think that the let statement let (x = 2, y = x) { print(y); } should desugar to exactly (function(x, y) { print(y); })(2, x) Also the let expression z = let (x = 2, y = x) x + y; should desugar to exactly z = (function(x, y) x + y)(2, x); The reasons for these particular desugarings is this is exactly what JavaScript programmers are writing today. It is common to see something like the desugared let statement above when looping and attaching event handlers to DOM elements, for example. I also think that since the name is "let" that the above desugaring makes sense as the closest analogy to Scheme's let. It doesn't make sense to me to have JavaScript's let be Scheme's let* or letrec. All these lets are purely sugar coatings and I'm not opposed to having Scheme's let* and letrec added to JavaScript as they introduce even sweeter sugar for some situations. I suppose let* would need to be renamed. Peter _______________________________________________ Es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
