programming languages - What is the meaning of the type "NONE" (like int,bool,string...) -


i have seen type none in book no explanation... understood type in languages wish understand in depth! void? or null?

the book called "programming language concepts , paradigms" (writen david a.watt) , has "wide view" of many languages , differences between 1 another. in languages use none (except python)? more 1 purpose nonetype?

thanks! amihay

python has nonetype none value. none similar null in other languages.

>>> type(none) <type 'nonetype'>

other languages may use none mean else.


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