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  1. c# - What does null! statement mean? - Stack Overflow

    Feb 16, 2019 · 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 …

  2. What is the purpose of null? - Stack Overflow

    Feb 25, 2009 · 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 …

  3. 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.

  4. javascript - Why is null an object and what's the difference between ...

    Apr 29, 2009 · 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 …

  5. What's the difference between " = null" and " IS NULL"?

    May 1, 2010 · Understanding the difference between “IS NULL” and “= NULL” When a variable is created in SQL with the declare statement it is created with no data and stored in the variable table …

  6. What is null in Java? - Stack Overflow

    Apr 25, 2010 · What is null? Is null an instance of anything? What set does null belong to? How is it represented in the memory?

  7. sql - Not equal <> != operator on NULL - Stack Overflow

    Apr 14, 2011 · 135 NULL has no value, and so cannot be compared using the scalar value operators. In other words, no value can ever be equal to (or not equal to) NULL because NULL has no value. …

  8. Why does NULL = NULL evaluate to false in SQL server

    Dec 4, 2009 · 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 …

  9. What is the difference between NULL, '\0' and 0? - Stack Overflow

    In C, there appear to be differences between various values of zero -- NULL, NUL and 0. I know that the ASCII character '0' evaluates to 48 or 0x30. The NULL pointer is usually defined as: #define

  10. How can I check for an undefined or null variable in JavaScript?

    The one benefit I can see is that it does not require knowing that == null and != null treat a declared variable with value undefined as equal to null. IMHO, that isn't reason enough to use this unfamiliar …