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Say I have a function that I would like reuse as a method on a couple objects in order to add data to those objects.

function addToObject(data) {
  for (var d in data) {
    if (data.hasOwnProperty(d)) {
      this[d] = data[d];
    }
  }
}

myObjOne = {
  add: addToObject
};

myObjTwo = {
  add: addToObject
};

My goal here was to be able to call myObjOne.add(myData) where myData is an object that I would like to add to myObjOne and be able to replicate this functionality on myObjTwo.

My issue is that using this within addToObject gives me:

this[d] = data[d];
^ Possible strict violation.

in jshint.

Why is this?

Trav McKinney
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1 Answers1

1

The docs say the warning happens when:

you use this in a non-constructor function. If you forget to use the new keyword when calling a constructor function, this will be bound unexpectedly to the global object in non-strict mode, but will be undefined in strict mode.

Use validethis:true in a pragma comment:

function addToObject(data) {
    'use strict';
    var d;
    for (d in data) {
        if (data.hasOwnProperty(d)) {
            /* jshint: validthis:true */
            this[d] = data[d];
        }
    }
}

References

Paul Sweatte
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  • But what does the warning mean? – nnnnnn Dec 18 '14 at 22:13
  • The docs say the warning happens when: `you use this in a non-constructor function`. If you forget to use the `new` keyword when calling a constructor function, `this` will be bound unexpectedly to the global object in [non-strict mode](http://www.yuiblog.com/blog/2010/12/14/strict-mode-is-coming-to-town/), but will be `undefined` in strict mode. – Paul Sweatte Dec 18 '14 at 23:04