Add Read In The Contents Of A File as a Deno til

README.md

@@ -10,7 +10,7 @@ pairing with smart people at Hashrocket.
 
 For a steady stream of TILs, [sign up for my newsletter](https://crafty-builder-6996.ck.page/e169c61186).
 
-_1174 TILs and counting..._
+_1175 TILs and counting..._
 
 ---
 
@@ -21,6 +21,7 @@ _1174 TILs and counting..._
 * [Chrome](#chrome)
 * [Clojure](#clojure)
 * [CSS](#css)
+* [Deno](#deno)
 * [Devops](#devops)
 * [Elixir](#elixir)
 * [Gatsby](#gatsby)
@@ -142,6 +143,10 @@ _1174 TILs and counting..._
 - [Style A Background With A Linear Gradient](css/style-a-background-with-a-linear-gradient.md)
 - [Using Maps In SCSS](css/using-maps-in-scss.md)
 
+### Deno
+
+- [Read In The Contents Of A File](deno/read-in-the-contents-of-a-file.md)
+
 ### Devops
 
 - [Aliasing An Ansible Host](devops/aliasing-an-ansible-host.md)

deno/read-in-the-contents-of-a-file.md

@@ -0,0 +1,23 @@
+# Read In The Contents Of A File
+
+Deno offers some nice utilities out of the box like reading in the contents of
+a file from the filesystem. The `readTextFile` function is available on the
+`Deno` object.
+
+```typescript
+// Read a file using Deno
+const text: string = await Deno.readTextFile("./first_input.txt");
+```
+
+You use a top-level await with the function call and, assuming the file exists,
+it will read the contents in. In this case, I assign them to the `text`
+variable.
+
+For the file reading to work when the program is executed, you must use the
+`--allow-read` flag.
+
+```bash
+$ deno run --allow-read program.ts
+```
+
+[source](https://deno.land/manual@v1.14.0/examples/read_write_files)