Correct scope outside a function in Javascript

Question

My question is regarding the below code:

var z='1'; 
(function(){ 
   y='2'; 
   console.log(z+y); // '12'
})();
console.log(z+y); // '12'

How come 'y' is accessible outside the function's scope?

Because it is global...variables declared without var keyword are global variables..var z='1'; (function(){ var y='2'; console.log(z+y); })(); console.log(z+y); will throw error Uncaught ReferenceError: y is not defined — Rayon
– Rayon, Commented Feb 29, 2016 at 10:17
with "var" like var z='1' is local and without "var" like y='2' is global. — Niklesh Raut
– Niklesh Raut, Commented Feb 29, 2016 at 10:19
y is global variable..if u want to prevent then u should use var — Rajesh Patel
– Rajesh Patel, Commented Feb 29, 2016 at 10:20

kemiller2002 · Accepted Answer · 2016-02-29 10:20:40Z

3

You declared y like this y='2'; By not putting the var keyword in front of it, the variable automatically becomes global.

answered Feb 29, 2016 at 10:20

kemiller2002

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Comments

Sultan · Accepted Answer · 2016-02-29 11:22:39Z

0

Key word without a var in front of it is declared as global variable.

answered Feb 29, 2016 at 11:22

Sultan

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