null and undefined both return false . That’s why your code is actually checking if false is equal to false . However their types are not equal. Because of that, the next statement will return false, as the === comparison operator checks both the types and their value.
Strict equality and undefined
You can use undefined and the strict equality and inequality operators to determine whether a variable has a value.
Is undefined == null?
Simply put, undefined means a variable has been declared but has not yet been assigned a value. … Here as the variable is declared but not assigned to any value, the variable by default is assigned a value of undefined. On the other hand, null is an object.
Is null undefined?
null is an assigned value. It means nothing. undefined means a variable has been declared but not defined yet. null is an object.
Is it better to return null or undefined?
Undefined typically refers to something which has not yet been assigned a value (yet). Null refers to something which definitively has no value. In that case, I would recommend returning a null. Note that a function with no specified return value implicitly returns undefined.
What is difference between null and null?
Null has a default value 0. it can be used as bool,integer, pointer. But C# null is used when we are not pointing to some object. I am not sure whether null can be used in place of NULL in C#.
How do I check if a Typecript is undefined?
You can check if it’s is undefined first. In typescript (null == undefined) is true. This is only half correct: 1) null and undefined DO have types in TypeScript.
Is truthy undefined?
Is null equal to undefined?
Summary. null is an assigned value. It means nothing. undefined typically means a variable has been declared but not defined yet.
Why is null undefined?