1.function does create new scope. 2.the (function(){})() run immedatly. 3.(function(){}) inside for block actually isclosurewhich does remeber the local var value (in our case is var j).
In JavaScript we have Function Scope and Lexical Scope. FunctionScopemeans that any variable which is defined within a function is visible within thatentire function. Block Scope, in which a variable scope is limited by the block a variable is declared in. A block is usual{curly brace} or l...
1.function does create new scope. 2.the (function(){})() run immedatly. 3.(function(){}) inside for block actually isclosurewhich does remeber the local var value (in our case is var j).
try { undefined(); // 执行一个非法操作来强制制造一个异常 } catch (err) { console.l...
块级作用域是函数作用域的补充；是比函数更小更灵活范围的作用域；js天生就俩(全局和局部，局部在js...
块级作用域是函数作用域的补充；是比函数更小更灵活范围的作用域；js天生就俩(全局和局部，局部在js...
JavaScript Function Variable Scope JavaScript Hoisting JavaScript Recursion JS Objects JavaScript Objects JavaScript Methods & this JavaScript Constructor JavaScript Getter and Setter JavaScript Prototype JS Types JavaScript Array JS Multidimensional Array JavaScript String JavaScript for...in loop JavaScript Number...
4:0 error "foo" used outside of binding context block-scoped-var 6:7 error "foo" used outside of binding context block-scoped-var By looking at the rules, I found that the identifier for the function is declared in the scope of the function and not its parent. Which means the functi...
JavaScript supports nested functions. Nested functions have access to the scope "above" them. Example The inner functionplus()has access to thecountervariable in the parent function: functionadd() { letcounter =0; functionplus() {counter +=1;} ...
This is the second part of my three-parter on JavaScript function methods. Last time I talked about call(). This time I’ll talk about apply(). apply(), like...