# Receivers and Extensions

DevFeed: [Receivers and Extensions](<https://devfeed.tech/articles/receivers-and-extensions-25062.md>)

Original publisher: [Read original article](<https://typealias.com/start/kotlin-receivers-and-extensions/>)

Author: author@typealias.com (Dave Leeds)

Published: 2022-06-13T00:00:00Z

Content type: tutorial

Language: en

Sources: [Dave Leeds on Kotlin - typealias.com](<https://devfeed.tech/sources/dave-leeds-on-kotlin-typealias-com.md>)

Topics: [Extension](<https://devfeed.tech/topics/extension.md>), [Kotlin](<https://devfeed.tech/topics/kotlin.md>)

Tags: [explicit-receiver](<https://devfeed.tech/tags/explicit-receiver.md>), [extension](<https://devfeed.tech/tags/extension.md>), [extension-function](<https://devfeed.tech/tags/extension-function.md>), [extension-property](<https://devfeed.tech/tags/extension-property.md>), [extensions](<https://devfeed.tech/tags/extensions.md>), [how-to](<https://devfeed.tech/tags/how-to.md>), [implicit-receiver](<https://devfeed.tech/tags/implicit-receiver.md>), [introduction](<https://devfeed.tech/tags/introduction.md>), [kotlin](<https://devfeed.tech/tags/kotlin.md>), [learn-to-program](<https://devfeed.tech/tags/learn-to-program.md>), [programming](<https://devfeed.tech/tags/programming.md>), [receiver](<https://devfeed.tech/tags/receiver.md>)

## AI overview

A Kotlin tutorial chapter explaining how extensions add functions and properties to existing classes. It introduces explicit and implicit receivers, extension functions, and extension properties.

## Source excerpt

Kotlin extensions can be used to add new functions and properties to existing classes--even to classes that you didn't write! In this chapter, we'll cover explicit receivers, implicit receivers, extension functions, and extension properties. Buckle up! Standalone Functions and Object Functions Way back in Chapter 2, we learned how to create functions. Here's a very simple function that puts single quotes at the beginning and the end of a String.