Isn’t the behaviour of closures in AS3 the same as in Java Script ? Yes, JavaScript does exactly the same thing. As does Python. And others. Although you define ‘var imageData’ inside the ‘for’, for loops do not introduce a new scope in these languages; in fact the variable imageData is bound in the containing … Read more
The [weak self] in anotherFunctionWithTrailingClosure is not needed. You can empirically test this: class Experiment { func someFunctionWithTrailingClosure(closure: @escaping () -> Void) { print(“starting”, #function) DispatchQueue.main.asyncAfter(deadline: .now() + 1) { closure() print(“finishing”, #function) } } func anotherFunctionWithTrailingClosure(closure: @escaping () -> Void) { print(“starting”, #function) DispatchQueue.main.asyncAfter(deadline: .now() + 1) { closure() print(“finishing”, #function) } } func … Read more
Found another solution with lexical-let (defun foo (n) (lexical-let ((n n)) #'(lambda() n))) (funcall (foo 10)) ;; => 10
The easiest way of finding out how it’s implemented is to try it. Write some code which uses a captured variable, compile it, then look at it in Reflector. Note that it’s the variable which is captured, not the value. That’s one of the big differences between Java and C# in this area. The basic … Read more
Use a “closure”: $(edit_link).click(function(){ return changeViewMode(myvar); }); This creates an anonymous temporary function wrapper that knows about the parameter and passes it to the actual callback implementation.
Overview Python doesn’t directly use variables the same way one might expect coming from a statically-typed language like C or Java, rather it uses names and tags instances of objects with them In your example, closure is simply an instance of a function with that name It’s really nonlocal here which causes LOAD_CLOSURE and BUILD_TUPLE … Read more
Yes, exactly. As you’ve identified, every function in JavaScript is a closure over at least one context: The global context. That’s how/why global variables work in JavaScript. We don’t normally call them closures unless they close over some other context and actually make use of the fact that they do, but you’re quite right that … Read more
Do you want the closure over the variable or the value? For example, package main import “fmt” func VariableLoop() { f := make([]func(), 3) for i := 0; i < 3; i++ { // closure over variable i f[i] = func() { fmt.Println(i) } } fmt.Println(“VariableLoop”) for _, f := range f { f() } … Read more
I’m not aware of anything built into JavaScript to reference local variables like that (though there probably should be considering all variables are internally referenced by strings). I’d suggest keeping all your variables in an object if you really need to access by string: var variables = { “j”: 1 }; alert(variables[“j”]); Update: It kind … Read more