fix: 🐛 add bare: true to coffee compiler

✅ Closes: Closes #134

README.md

@@ -577,6 +577,12 @@ input(bind:value="{foo}")
 input(on:input="{bar}")
 ```
 
+### `coffeescript`
+
+#### Safety wrapper
+
+Since `coffeescript` transpiles variables to `var` definitions, it uses a safety mechanism to prevent variables from bleeding to outside contexts. This mechanism consists of wrapping your `coffeescript` code inside an IIFE which, unfortunately, prevents `svelte` from finding your variables. To bypass this behavior, `svelte-preprocess` sets the [`bare` coffeescript compiler option](https://coffeescript.org/#lexical-scope) to `true`.
+
 ## FAQ
 
 ### My VS Code is displaying a lot of errors on my templates when I try to use `x`...

src/transformers/coffeescript.ts

@@ -10,6 +10,7 @@ const transformer: Transformer<Options.Coffeescript> = ({
   const { js: code, sourceMap: map } = coffeescript.compile(content, {
     filename,
     sourceMap: true,
+    bare: false,
     ...options,
   });