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