String templates and interpolation in Kotlin - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a string template in Kotlin?

A string template in Kotlin is a way to include variables or expressions inside a string by using the $ symbol before the variable name or ${} for expressions.

beginner

How do you include a variable name inside a string using Kotlin string templates?

You write the string like this: "Hello, $name!". Kotlin replaces $name with the value of the variable name.

beginner

How do you include an expression like 2 + 3 inside a Kotlin string template?

You use curly braces around the expression: "The sum is ${2 + 3}". Kotlin calculates the expression and inserts the result.

intermediate

What happens if you want to include a literal dollar sign $ in a Kotlin string template?

You escape it by using \$. For example, "Price is \$5" will show Price is $5.

intermediate

Can you use string templates with multiline strings in Kotlin?

Yes! You can use string templates inside triple-quoted strings """...""". Variables and expressions inside $ or ${} will be replaced as usual.

How do you insert the value of a variable age into a Kotlin string?

A "I am $age years old"

B "I am age years old"

C "I am ${age}"

D "I am ${age years old}"

Use $age or ${age} to insert the variable value. Option A is correct and simplest.

What is the output of: val x = 5; println("x + 2 = ${x + 2}")?

A x + 2 = 5 + 2

B x + 2 = x + 2

C x + 2 = ${x + 2}

D x + 2 = 7

The expression inside ${} is evaluated, so it prints 7.

How do you write a literal dollar sign in a Kotlin string template?

A $$

B \$

C $

D \\$

Use a backslash before the dollar sign to escape it: \$.

Which of these is a valid Kotlin string template expression?

A "Hello, ${user.name!}"

B "Hello, $user.name!"

C "Hello, ${user.name}!"

D "Hello, $user.name!" with quotes

You must use ${} for expressions like accessing a property.

Can you use string templates inside triple-quoted strings in Kotlin?

A Yes, variables and expressions are replaced.

B No, string templates don't work in triple quotes.

C Only variables work, not expressions.

D Only expressions work, not variables.

Triple-quoted strings support string templates fully.

Explain how to use string templates in Kotlin to include variables and expressions inside strings.

Think about how you write a sentence with a variable inside.

Describe how to include a literal dollar sign character in a Kotlin string that uses string templates.

Remember that $ is special in string templates.