如果在if或loop里面,通常用operator,declaration无法实现因为他会被hoisted到最前面(除非没人用firefox访问你的脚本,因为在ff里这个会变成函数语句?)declarations在if或loop里面的兼容性不好。 如果你的函数只用一次,operator显然更简洁,对于单行jquery事件处理去修改一些css,operator很完美。 通
“Expected an assignment or function call and instead saw an expression.”:“需要一个语句或者一个函数调用,而不是一个表达式”, “Function declarations should not be placed in blocks. Use a function expression or move the statement to the top of the outer function.”:“函数的声明不能放在类似if...
Function declarations are hoisted, which means that it’s easy - too easy - to reference the f...
Hoisting applies to variable declarations and to function declarations. Because of this, JavaScript functions can be called before they are declared: myFunction(5); function myFunction(y) { return y * y; } Functions defined using an expression are not hoisted. ...
There’s one alternative to function declarations which is called function expressions, which we are about to cover. 只有这2个位置可以声明函数,也就是说:不可能在表达式位置或一个代码块中定义它。 另外一种可以取代函数声明的方式是函数表达式,解释如下: ...
Hoisting applies to variable declarations and to function declarations. Because of this, JavaScript functions can be called before they are declared: myFunction(5); functionmyFunction(y) { returny * y; } Functions defined using an expression are not hoisted. ...
There’s one alternative to function declarations which is calledfunction expressions, which we are about to cover. 只有这2个位置可以声明函数,也就是说:不可能在表达式位置或一个代码块中定义它。 另外一种可以取代函数声明的方式是函数表达式,解释如下: ...
declarations -miphoneos-version-min=6.0 -Wno-sign-conversion -fembed-bitcode-marker -I/Users/formalin14/green/opencv_ios/build/arm64-iPhoneOS/3rdparty/lib/Release/include -I/Users/formalin14/green/opencv_ios/build/arm64-iPhoneOS/3rdparty/zlib -I/Users/formalin14/green/opencv/3rdparty/zlib -I/...
This is related to the fact that classes in JavaScript are not hoisted like function declarations. Especially in ES6 where classes have TDZ (it is a static error to reference them before their declaration). The workaround is to declareautoserializableAsto take a function that returns the class...
letsession=('express-session');^SyntaxErrorBlockscopeddeclarationsletconstnot yet supported outside strict mode at exportsrunInThisContextvmjs:53:16)at Module._compile(module.js:373:25)at Object.Module_extensionsmodulejs416at Moduleloadmodule.js:343:32at Function.Module._load(module.js:300:12)at...