Explain difference between: function Person(){} , va...
Explain difference between: function Person(){} , va...
To answer the interview question regarding the differences between function Person(){}
, var person = Person()
, and var person = new Person()
, it's important to understand the context in which each is used in JavaScript, particularly focusing on function declarations, function calls, and object instantiation.
function Person(){}
:
Person
. It doesn't execute the function but merely sets up the function structure in memory. The function can be called later in the code. This function, when called, will execute the code block defined within its braces {}
. If used with the new
keyword, it can act as a constructor to create new objects.var person = Person()
:
Person
and assigns its return value to the variable person
. If the Person
function does not explicitly return a value, person
will be assigned undefined
. This usage does not involve object creation directly unless the Person
function itself returns an object. This is a simple function call and is not used for creating an instance of an object in the context of object-oriented programming.var person = new Person()
:
Person
function as...senior
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