Variable declaration using var in Go - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the var keyword do in Go?

It declares a variable with a specified type and optionally assigns it a value.

beginner

How do you declare an integer variable named age using var?

You write:

var age int

This creates a variable age of type int with a default value 0.

intermediate

Can you declare multiple variables at once using var? How?

Yes. Use parentheses and list variables:

var (
  x int
  y string
)

This declares x as int and y as string.

beginner

What is the default value of a variable declared with var but not assigned?

It depends on the type: <br>- Numbers: 0 <br>- Strings: empty string <br>- Booleans: false <br>- Pointers: nil

beginner

How to declare and assign a variable in one line using var?

Write:

var name string = "Alice"

This declares name as string and assigns "Alice".

What is the correct way to declare a variable count of type int using var?

A var count int

B count := int

C int var count

D var int count

The correct syntax is var count int to declare an int variable.

What is the default value of a string variable declared with var but not assigned?

A nil

B empty string

C 0

D false

Strings default to an empty string "" when declared but not assigned.

Which of these declares multiple variables correctly?

A var x, y int

B var (x int, y string)

C var x int; y string

D var ( x int y string )

Both var x, y int and using parentheses with new lines: var ( x int y string ) are correct.

How do you declare and assign a variable name with value "Bob" using var?

A name := "Bob"

B var name = "Bob"

C var name string = "Bob"

D var string name = "Bob"

The full declaration with type and assignment is var name string = "Bob".

What happens if you declare a variable with var but do not assign a value?

A It keeps old memory value

B It causes an error

C It is nil always

D It has a zero value depending on type

Variables declared with var get a zero value based on their type automatically.

Explain how to declare a variable using var in Go and what happens if you don't assign a value.

Think about how Go handles variables when you only declare them.

Describe how to declare multiple variables at once using var and why it might be useful.

Consider grouping declarations for neatness.