Fix windows_subsystem usage description.

johnthagen · johnthagen · commit dfb25a7c07ee · 2017-06-13T12:23:01.000-04:00
diff --git a/_posts/2017-06-08-Rust-1.18.md b/_posts/2017-06-08-Rust-1.18.md
@@ -77,15 +77,15 @@ For our Windows users, Rust 1.18.0 has [a new attribute,
 works like this:
 
 ```rust
-#![windows_subsystem(console)]
-#![windows_subsystem(windows)]
+#![windows_subsystem = "console"]
+#![windows_subsystem = "windows"]
 ```
 
 These control the [`/SUBSYSTEM` flag](https://msdn.microsoft.com/en-us/library/fcc1zstk.aspx)
-in the linker. For now, only `console` and `windows` are supported.
+in the linker. For now, only `"console"` and `"windows"` are supported.
 
 When is this useful? In the simplest terms, if you're developing a graphical
-application, and do not specify `windows`, a console window would flash up upon
+application, and do not specify `"windows"`, a console window would flash up upon
 your application's start. With this flag, it won't.
 
 Finally, Rust's tuples, enum variant fields, and structs (without `#[repr]`) have
