Re-Declaring JavaScript Variables

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Re-Declaring JavaScript Variables

@mukesh.tomar

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about 9 years ago
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In javascrit,if you re-declare a variable, it wouldn't lose it value.

Example ->
```
var a=10;
var a;
alert(a);
```
Output : 5

Here you can see, in JavaScript the output will be same but in other languages result would be undefined or NaN.

Advantage :
Re-declaring a variable is useful in those situation where it is not known ,if the variable has already been defined.
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Re-declaring variable in javascript
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4 Comment(s)

@JamesSprag

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over 2 years ago
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this is very useful for me, thanks!

@mukesh.tomar

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about 9 years ago
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Hello Sir , If the variable is declared in a global scope and then re-declared in a function then its scope remains in that function only and global variable doesn't effect from this .

@sumeet

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about 9 years ago
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We'll Interesting but what about scope in javascript variable from global to function scope...

@kumar.abhishek

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about 9 years ago
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helped alot

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