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What happens when a variable is declared with var?
Duplicate variable declarations using var will not trigger an error, even in strict mode, and the variable will not lose its value, unless another assignment is performed. Variables declared using var are created before any code is executed in a process known as hoisting.
How are var declarations processed in JavaScript code?
var declarations, wherever they occur, are processed before any code is executed. This is called hoisting, and is discussed further below. The scope of a variable declared with var is its current execution context, which is either the enclosing function or, for variables declared outside any function, global.
Why is var declared as a non configurable property?
In the global context, a variable declared using var is added as a non-configurable property of the global object. This means its property descriptor cannot be changed and it cannot be deleted using delete.
Where is a variable declared in Visual Basic?
For variable naming rules and considerations, see Declared Element Names. A local variable is one that is declared within a procedure. A member variable is a member of a Visual Basic type; it is declared at module level, inside a class, structure, or module, but not within any procedure internal to that class, structure, or module.
What is the default value of a Var in JavaScript?
It can be any legal expression. Default value is undefined . Alternatively, the Destructuring Assignment syntax can also be used to declare variables. var declarations, wherever they occur, are processed before any code is executed. This is called hoisting, and is discussed further below.
What does it mean to scope a variable in JavaScript?
This is called hoisting, and is discussed further below. The scope of a variable declared with var is its current execution context and closures thereof, which is either the enclosing function and functions declared within it, or, for variables declared outside any function, global.