# Async / await Async / await is a pattern that can be used for managing asynchronus functions, i.e functions that don't complete each function call in order of calling, but rather based on when the task is finished executing. Working with this pattern in JavaScript typically looks like using Promises and callbacks, and modern JavaScript uses two new keywords to manage this: async, which specifies that a function can use await, and await, which specifies that the function should wait until the function provided is finished executing before moving on. Derw handles this through the use of `do..return`, blocks which can exist within functions, similarly to `let..in` blocks. The main difference is that `do..return` blocks can have top level function calls (i.e without needing to assign the result to a const or a function). Each function call within a do..return block waits until has finished executing before continuing. This means that the order of definitions matter. Under the hood, these are compiled to async/await JS blocks. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.derw-lang.com/hypotheticals/async-await.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.