You do not know the JS series (19) - this call position

We excluded some of this misunderstanding and to understand , it depends entirely on the function of this position call each function is invoked when bound . Looking call position is looking for "location function is called," but doing it is not so simple, because some of the programming mode may hide the real location of the call

 

The most important thing is to analyze the call stack, it is to reach all functions called by the current execution position

function baz () { // call position is a global scope, the call stack baz 
　　the console.log ( 'baz' );
　　bar (); // bar call sites 
}
 function bar () { // call baz position in the call stack baz -> bar 
　　the console.log ( 'bar' );
　　foo (); // foo call sites 
}
 function foo () { // call site bar in the call stack baz -> bar -> foo 
　　the console.log ( 'foo' );
}
baz (); // baz call sites

The call stack can be thought of as a chain of function calls, but this method is very cumbersome and error-prone. Another approach is to view the call stack using the browser debugging tools. Sources inside the Call Stack; use development tools to get the call stack, the stack and then find the second element, is the real calling location.