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Add New Dates Can Take Out Of Bounds Values as a javascript til

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2018-02-16 13:29:14 -06:00
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# New Dates Can Take Out Of Bounds Values
You can create a new date by feeding it arguments for _year_, _month_, and
_day_.
```javascript
> new Date(2017, 11, 31)
Sun Dec 31 2017 00:00:00 GMT-0600 (CST)
```
What happens if we push the _day_ value out of bounds?
```javascript
> new Date(2017, 11, 32)
Mon Jan 01 2018 00:00:00 GMT-0600 (CST)
```
It rolls over to the next month.
Does the same happen when we push the _month_ value out of bounds?
```javascript
> new Date(2017, 12, 31)
Wed Jan 31 2018 00:00:00 GMT-0600 (CST)
```
Yep.
What about negative values?
```javascript
> new Date(2018, -1, 31)
Sun Dec 31 2017 00:00:00 GMT-0600 (CST)
```
It rolls the month, and consequently the year, back.