Reference Error in javascript plugin

Question

I am creating some basic plugin and i am getting Reference error. Below is my code

jQuery.fn.validate = function(options) {
  var _self = this;
   // with below call I gets reference error.
  abc();  

    //but if call in below it works fine
  _self.on("submit", function(event) {
     abc();  // works fine
  }),

 abc = function () {
   console.log('here);
 }
};

Can someone explain why I am getting this error and how to overcome it. As i need to call some reset and init functions at the begining of the plugin.

You're calling abc() before you have declared it, move the call to abc() below where you declare abc = function() — Ryan Wilson, Mar 29 '18 at 20:00
You shouldn't define global names in a plugin, you should make `abc` a local name. — Barmar, Mar 29 '18 at 20:02
Possible duplicate of [var functionName = function() {} vs function functionName() {}](https://stackoverflow.com/questions/336859/var-functionname-function-vs-function-functionname) — Taplar, Mar 29 '18 at 20:03
@Barmar what do you mean by local name ? Can you give me example ? — Aman jaura, Mar 29 '18 at 20:39

score 1 · Accepted Answer · answered Mar 29 '18 at 20:03

1

It seems like you're expecting abc to be hoisted, but you're specifically using a syntax that leaves abc undefined until the assignment is executed.

You need to move abc = function ... up above the invocations of abc(), or define the function using function abc() { } which will allow it to be hoisted above your invocations.

Note that, if you simply move the assignment, you should use var abc = function ... and create a local variable, rather than the global abc variable you're currently creating.

answered Mar 29 '18 at 20:03

user229044

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ok i got your point but it works when i call _self.on("submit", function(event) { abc(); // works fine }), – Aman jaura Mar 29 '18 at 20:05
@Amanjaura Because that is invoked after your assignment, at some point in the future when a button is clicked and that callback is invoked. – user229044 Mar 29 '18 at 20:06
So which approach should i use in plugins while creating function `abc = functions` or `function abc()` ? Or is there any better solution on how to create and initialize functions in js plugin. Anyhow thanks for the above explanation. – Aman jaura Mar 29 '18 at 20:10

Reference Error in javascript plugin

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