1. Alternative to Object Oriented programming In theory, anywhere you can use a class/constructor you can use a closure instead. They both essentially perform the same thing: encapsulate data and maintain state – but via different mechanisms. Objects maintain state using context (Java calls it “scope” but because Java does not actually have real scopes) … Read more
greet is a closure. A computed property is var greet : Int { return 4+3 } greet // without parentheses And “in” in closure is also not compulsory if a parameter is passed (by the way the return keyword is not compulsory) var greet = { x in 4+x } greet(4) unless you use the … Read more
Sure, you can do: def italic(predecessor): x = predecessor def successor(): return “<italic/>” + x() + “</italic>” return successor Just like you can do: def italic(predecessor): x = predecessor x2 = x def successor(): return “<italic/>” + x2() + “</italic>” return successor or def italic(predecessor): x = predecessor x2 = x x3 = x2 def … Read more
The reason for this is that every counter(7) call creates a separate count instance and separate incr function. When you call them, you actually refer to different variables count thus the results are as shown above. 2 solved Below code is weird
I’ve never actually seen PyFunction_SetClosure used, but I would expect to use it for modifying an existing Python function object to change the closure variables. It probably isn’t suitable for implementing a generating a new function with a closure from scratch, because that would not be implemented in terms of PyFunctionObject (since these are specifically … Read more
A closure is a pairing of: A function and A reference to that function’s outer scope (lexical environment) A lexical environment is part of every execution context (stack frame) and is a map between identifiers (i.e. local variable names) and values. Every function in JavaScript maintains a reference to its outer lexical environment. This reference … Read more
Well, the problem is that the variable i, within each of your anonymous functions, is bound to the same variable outside of the function. ES6 solution: let ECMAScript 6 (ES6) introduces new let and const keywords that are scoped differently than var-based variables. For example, in a loop with a let-based index, each iteration through … Read more