As someone who always disliked Objective C, I think Swift looks very promising. I'll check it out right away :) Software-wise, I feel these current WWDC announcements are the most exciting in years. Looking at the Swift docs right now, I can see many interesting inspirations at work: there's some Lua/Go in there (multiple return values), some Ruby (closure passed as the last argument to a function can appear immediat…
> It has the concept of explicitly capturing variables from the surrounding context inside closures, like PHP does, instead of keeping the entire context alive forever like Ruby or JS. Just as a point of fact, javascript -- at least the v8 implementation I'm most knowledgeable of -- doesn't "keep the entire context alive forever." Only variables used in the closure are allocated into the closure (i.e. on the heap), t…
I'm not sure that's true. Look at the following code:
var x = 123;
var f = function(xname) {
eval('console.log('+xname+');');
}
f('x');
This means in Javascript, as well as in Ruby, when you hand a closure to my code, I can access the entire environment of that closure.
Contrast that with Lua, for example, where the compiler does indeed check whether an outer variable is being used and then it imports that variable from the context only.
PHP does it most explicitly, forcing the developer to declare what outer objects they want to have available within the function.