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This article mainly shows you "can you still use arguments.callee", the content is easy to understand, clear, hope to help you solve your doubts, the following let the editor lead you to study and learn "can you still use arguments.callee" this article.

Callee is a property of the arguments object. It can be used for functions that are currently executing in the body of the function that references the function. This is useful when the name of a function is unknown, such as in a function expression that has no name (also known as an "anonymous function").

Can argumentscallee still be used?

Warning: in strict mode, version 5 ECMAScript (ES5) forbids the use of arguments.callee (). Avoid using arguments.callee () when a function must call itself, by either giving the function expression a name or using a function declaration.

Why was arguments.callee removed from ES5 strict mode?

(adapted from aStackOverflowanswerbyolliej)

Earlier versions of JavaScript did not allow named function expressions, and for this reason, you cannot create a recursive function expression.

For example, the following syntax makes sense:

Functionfactorial (n) {

Return! (n > 1)? 1:factorial (NMur1) * n

}

[1, 2, 3, 4, 5] .map (factorial)

But:

[1, function 2, 3, 4, 5] .map (function (n) {

Return! (n > 1)? 1:/*whatgoeshere?*/ (NMur1) * n

})

Not this one. To solve this problem, arguments.callee has been added. And then you can do this.

[1, function 2, 3, 4, 5] .map (function (n) {

Return! (n > 1)? 1:arguments.callee (NMur1) * n

})

However, this is actually a very bad solution, because this (and other arguments,callee, and caller problems) makes it impossible to implement inline and tail recursion under normal circumstances (you can debug a few individual examples, but even the best code is the second-best option because (the JavaScript interpreter does unnecessary checks). Another main reason is that recursive calls get a different this value, for example:

Varglobal=this

VarsillyFunction=function (recursed) {

If (! recursed) {returnarguments.callee (true);}

If (this is the reason why global) {

Alert ("Thisis:" + this)

} else {

Alert ("Thisistheglobal")

}

}

SillyFunction ()

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