What happens when you declare a variable in JavaScript twice?

Can we declare a variable multiple times?

Declaring multiple variables in a single declaration can cause confusion regarding the types of the variables and their initial values. …

How many times can you declare a variable?

A variable or function can be declared any number of times, but it can be defined only once. (Remember the basic principle that you can’t have two locations of the same variable or function).

How many times can you initialize a variable and how many times can you declare a variable?

a variable/function can be declared any number of times but it can be defined only once [duplicate] Closed 2 years ago. a variable/function can be declared any number of times but it can be defined only once.

Is it true that functions are called once but can be declared many times?

A variable or a function can be declared any number of times but, it can be defined only once. … This declaration is just for informing the compiler that a function named f with return type and argument as int will be used in the function.

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Is multiple declaration allowed in C?

In C and C++, int y; within a function is both a declaration and a definition. In C, int x; in the file scope (outside any function) is a declaration and a tentative defintion. Multiple tentative definitions are allowed; only one definition is allowed.

Can you declare variables in one line?

You can declare multiple variables of the same type in one line of code: int a, b, c; You can also assign multiple variables to one value: … This code will set c to 5 and then set b to the value of c and finally a to the value of b .

How do we identify Java variables?

Use getClass(). getSimpleName() to Check the Type of a Variable in Java. We can check the type of a variable in Java by calling getClass(). getSimpleName() method via the variable.

What is difference between VAR and let in Javascript?

var and let are both used for variable declaration in javascript but the difference between them is that var is function scoped and let is block scoped. It can be said that a variable declared with var is defined throughout the program as compared to let.

What happens if I use a variable before initializing it to a value?

Accessing the value of the variable will give you the contents of that piece of memory. However until the variable is initialised, that piece of memory could contain anything. This is why using it is unpredictable.

Is it possible to initialize a variable at the time it was declared?


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Neither variable is pre-initialized. The value of each variable is printed out using a printf() statement. It can be seen from the sample output that the values which each of the variables take on at declaration time are no-zero.

What is the difference between declaring and initializing a variable?

Declaration tells the compiler about the existence of an entity in the program and its location. When you declare a variable, you should also initialize it. Initialization is the process of assigning a value to the Variable. … If the value is not assigned to the Variable, then the process is only called a Declaration.

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