No JavaScript overload concept

Question

Check the fiddle or code below:

 function abc(s) {
     console.log('in abc(s)');
 }

 function abc(s, t) {
     console.log('in abc(s,t)');
 }

 abc('1');

The output of this question is always in abc(s,t)

Can someone please explain to me what is happening here and why?

Answer 1

First, support for the overload method is not supported in JavaScript (see @ 6502 workaround ).

Secondly, to describe what you are experiencing in JavaScript, the last declared function (with the same name) is called, because the first has been overwritten, it refers to Raising JavaScript .

Try changing the order of function declarations and see the output again:

 function abc(s, t) {
     console.log('in abc(s,t)');
 }

function abc(s) {
     console.log('in abc(s)');
 }

 abc('1');

Answer 2

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function abc(s, t) {
    // test to see if the t argument was passed
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    }
}

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abc('1', '2');  // outputs 'was called as abc(s,t)'

---

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---

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