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c# - What does null! statement mean? - Stack Overflow
It can be used on a type to control Nullability, it is then called the "Null Forgiving Operator" Basically, null! applies the ! operator to the value null This overrides the nullability of the value null to non-nullable, telling the compiler that null is a "non-null" type
Why does NULL = NULL evaluate to false in SQL server
The expression "NULL = NULL" evaluates to NULL, but is actually invalid in SQL; yet ORDER BY treats NULLs as equal (whatever they precede or follow "regular" values is left to DBMS vendor)
What is the difference between is not null and != null?
The main difference between e != null and e is not null is the way the the compiler executes the comparison Microsoft: "The compiler guarantees that no user-overloaded equality operator == is invoked when expression x is null is evaluated " Bottom Line: If you are writing code that you don't want to depend on someone's implementation of the != and == operators, use is null and is not null
javascript - Why is null an object and whats the difference between . . .
In order to be able to query this difference, JavaScript has null and undefined: While null is - just like in other languages an object, undefined cannot be an object because there is no instance (even not a null instance) available
How do I check for null values in JavaScript? - Stack Overflow
How can I check for null values in JavaScript? I wrote the code below but it didn't work
What is the purpose of null? - Stack Overflow
Null: The Billion Dollar Mistake Tony Hoare: I call it my billion-dollar mistake It was the invention of the null reference in 1965 At that time, I was designing the first comprehensive type system for references in an object oriented language (ALGOL W) My goal was to ensure that all use of references should be absolutely safe, with checking performed automatically by the compiler But I
c# - Math operations with null - Stack Overflow
The operators for Nullable<T> are so-called "lifted" operators]; the c# compiler takes the operators available for T and applies a set of pre-defined rules; for example, with +, the lifted + is null if either operand is null, else the sum of the inner values Re the last; again, division is defined as null if either operand is null - it never performs the division
JavaScript checking for null vs. undefined and difference between . . .
How do I check a variable if it's null or undefined and what is the difference between the null and undefined? What is the difference between == and === (it's hard to search Google for "===" )?