Merge pull request #4103 from shaedrich/async-await

Add topic "async/await"

Author: kenyonj

topics/async-await/index.md

@@ -0,0 +1,9 @@
+---
+topic: async-await
+display_name: async/await
+short_description: async/await allows an asynchronous, non-blocking function to be structured in a way similar to an ordinary synchronous function.
+related: callback, coroutines, async, promise, future, actor-model, continuation-passing-style, concurrent-computing
+released: 2007
+wikipedia_url: https://en.wikipedia.org/wiki/Async/await
+---
+In computer programming, the **async/await** pattern is a syntactic feature of many programming languages that allows an asynchronous, non-blocking function to be structured in a way similar to an ordinary synchronous function, and is primarily intended to provide opportunities for the program to execute other code while waiting for a long-running, asynchronous task to complete, usually represented by promises or similar data structures.