isDef

This function returns true if its argument is neither null nor undefined.

Why

I'm tired of always writing the same function of a single line in all my projects so I add it in npm. This function is eslint OK.

Integration for browser

To integrate it into your project, different ways: add the 3 lines of code below.

<script>
   window.isDef = function(obj) {
       return (obj !== null && typeof obj !== "undefined");
   }
</script> 

or

npm install isnotnull --save

then references like this

    <script>node_modules/isnotnull/distrib/isdef.min.js</script> 

or

npm install isnotnull --save

then with gulp, you can concatenate your sources and include "node_modules/isnotnull/distrib/isdef.min.js"

Integration for Node.js

npm install isnotnull --save

const isDef=require("isnotnull");

usage

When using isdef in your sources, add the tag /* global isDef */ to pass eslint validation.

example

 
<script>
    /* global isDef */
 
    var var1 = null;
    isDef(var1); // false
    isDef(var2); // false
 
    var obj = {a:1};
    isDef(obj); // true
    isDef(obj.b); // false
</script>