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Avinash Chodavarapu
Avinash Chodavarapu

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Variables and Constants: Declaration and Usage

Explanation of how to declare and use variables and constants in Go.

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Go is a statically typed programming language that requires variables to be declared with a specific data type. Variables can be declared using the var keyword followed by the variable name and data type.



var age int



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Here, age is the variable name and int is the data type. Variables can also be initialized with a value at the time of declaration.



var age int = 25



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In Go, constants are declared using the const keyword followed by the constant name and value.



const pi = 3.14



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Constants can also be declared with a data type.



const pi float64 = 3.14



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There are multiple ways to declare variables and constants in Go:

  • Declare and initialize a single variable or constant in a single statement.


var age int = 25
const pi float64 = 3.14



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  • Declare and initialize multiple variables or constants in a single statement.


var name, age = "John Doe", 25
const pi, gravity = 3.14, 9.81



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  • Declare and initialize a variable or constant using shorthand notation.


name := "John Doe"
const pi = 3.14



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In Go, it is possible to use variables and constants in expressions and statements. Here is an example:



var radius float64 = 5.0
const pi float64 = 3.14

var circumference = 2 * pi * radius



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In this example, the variable circumference is assigned the value of 2 * pi * radius.

In summary, variables and constants are used to store and manipulate data in Go programs. Variables can be changed during the execution of a program, while constants cannot. To declare a variable or constant, we use the "var" or "const" keyword followed by the name and type/value. To use a variable or constant, we refer to its name in our code.

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