How to check whether a uint256 is null in solidity?











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I want to check whether a uint256 variable is null. How can I do so in solidity?






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    You can check it by comparing with 0
    – A.K.
    Nov 21 at 8:09















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I want to check whether a uint256 variable is null. How can I do so in solidity?






solidity







share|improve this question


















  • 2




    You can check it by comparing with 0
    – A.K.
    Nov 21 at 8:09













up vote
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up vote
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down vote

favorite











I want to check whether a uint256 variable is null. How can I do so in solidity?






solidity







share|improve this question













I want to check whether a uint256 variable is null. How can I do so in solidity?






solidity




solidity






share|improve this question













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asked Nov 21 at 8:01









Rohan Dhar

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  • 2




    You can check it by comparing with 0
    – A.K.
    Nov 21 at 8:09














  • 2




    You can check it by comparing with 0
    – A.K.
    Nov 21 at 8:09








2




2




You can check it by comparing with 0
– A.K.
Nov 21 at 8:09




You can check it by comparing with 0
– A.K.
Nov 21 at 8:09










1 Answer
1






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There aren't any things like null in solidity.



All the uninitialized variables are set to a zero like value.



Have a look at this answer for more examples.






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    Indeed, but I'd add that integers do not normally have nulls in any programming language. They are primitives.
    – Paul Berg
    Nov 21 at 23:10











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1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes








up vote
5
down vote



accepted










There aren't any things like null in solidity.



All the uninitialized variables are set to a zero like value.



Have a look at this answer for more examples.






share|improve this answer

















  • 1




    Indeed, but I'd add that integers do not normally have nulls in any programming language. They are primitives.
    – Paul Berg
    Nov 21 at 23:10















up vote
5
down vote



accepted










There aren't any things like null in solidity.



All the uninitialized variables are set to a zero like value.



Have a look at this answer for more examples.






share|improve this answer

















  • 1




    Indeed, but I'd add that integers do not normally have nulls in any programming language. They are primitives.
    – Paul Berg
    Nov 21 at 23:10













up vote
5
down vote



accepted







up vote
5
down vote



accepted






There aren't any things like null in solidity.



All the uninitialized variables are set to a zero like value.



Have a look at this answer for more examples.






share|improve this answer












There aren't any things like null in solidity.



All the uninitialized variables are set to a zero like value.



Have a look at this answer for more examples.







share|improve this answer












share|improve this answer



share|improve this answer










answered Nov 21 at 8:09









Tudor Constantin

1,805212




1,805212








  • 1




    Indeed, but I'd add that integers do not normally have nulls in any programming language. They are primitives.
    – Paul Berg
    Nov 21 at 23:10














  • 1




    Indeed, but I'd add that integers do not normally have nulls in any programming language. They are primitives.
    – Paul Berg
    Nov 21 at 23:10








1




1




Indeed, but I'd add that integers do not normally have nulls in any programming language. They are primitives.
– Paul Berg
Nov 21 at 23:10




Indeed, but I'd add that integers do not normally have nulls in any programming language. They are primitives.
– Paul Berg
Nov 21 at 23:10


















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