我在1月12日发表了《解读ECMAScript[2]——函数、构造器及原型》一文,文中提到了函数声明(Function Declaration)与函数表达式(Function Expression)的概念。在那篇文章中,重点对两者与ECMAScript内置对象Function之间的关系进行了论述,而对两者的区别未加以详细说明。昨天晚上对Web前端颇有研究的jee.chang.sh同学在GTalk上...
JavaScript中Function Declaration与Function Expression 或者说 function fn(){}和var fn=function(){} 的区别 JavaScript是一种解释型语言,函数声明会在JavaScript代码加载后、执行前被解释,而函数表达式只有在执行到这一行代码时才会被解释。 在JS中有两种定义函数的方式, 1是:var aaa=function(){...} 2是:funct...
b) Function Expressions are more versatile. A Function Declaration can only exist as a “statement” in isolation. All it can do is create an object variable parented by its current scope. In contrast, a Function Expression (by definition) is part of a larger construct.If you want to crea...
functionf1(){console.log('f1');}f1();// 调用 函数表达式 Function Expression varf2=function(){console.log('f2');};// 注意有一个分号f2();// 调用 IIFE – Immediately-Invoked Function Expression // 构造一个匿名函数并立即调用(function(){console.log('f2');})();...
“Missing name in function declaration.”:“在中缺少名称”, “Expected an identifier and instead saw ‘{a}’.”:“需要有一个标识符,而不是’{a}’”, “Inner functions should be listed at the top of the outer function.”:“内部函数的声明应该放在此函数的顶部。”, ...
A function call is an expression that passes control and arguments (if any) to a function and has the form:expression (expression-listopt)where expression is a function name or evaluates to a function address and expression-list is a list of expressions (separated by commas). The values of...
看不明白
FunctionDeclaration FunctionExpression FunctionExpression Methods JScriptFunctionExpression FunctionObject FunctionPrototype FunctionWrapper GlobalObject Globals GlobalScope Hide IActivationObject IAuthorServices IColorizeText IDebugConvert IDebugConvert2 IDebuggerObject ...
You cannot self-invoke a function declaration. You have to add parentheses around the function to indicate that it is a function expression: Example (function() { letx ="Hello!!";// I will invoke myself })(); Try it Yourself » ...
If the decl-specifier-seq of the function declaration contains the keyword auto, trailing return type may be omitted, and will be deduced by the compiler from the type of the expression used in the return statement. If the return type does not use decltype(auto), the deduction follows the ...