when judging the parameter type today, we found that
Object.prototype.toString.call (param) can, and
Object.toString.call (param) cannot.
the error message is
Function.prototype.toString requires that "this" be a Function.
but the output of the two functions on the console should look the same. Excuse me, why is this?
Object constructor itself does not have a toString method.
according to the prototype chain relationship, the upstream prototype chain of the Object constructor is Function.prototype .
so, when you call Object.toString.call (param) , you essentially call Function.prototype.toString.call (param) . The parameter type required here is function , and you pass the object , so you will report an error.
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