In Astro, you can define local JavaScript variables inside of the frontmatter component script between the two code fences (---) of an Astro component. You can then inject these variables into the component’s HTML template using JSX-like expressions. However, you cannot directly pass a variable from a client-side script to the HTML content.
Here's an example of how you can define and use a variable in Astro:
---
const name = "Astro";
---
<div>
<h1>Hello {name}!</h1> <!-- Outputs <h1>Hello Astro!</h1> -->
</div>
(Source: Astro Documentation (https://docs.astro.build/en/core-concepts/astro-syntax#_top))
However, in your case, you're trying to use a variable that's defined in a client-side script. This is not directly possible because the script runs in the browser, while the Astro component is rendered on the server.
One way to pass data from the server to the client is to use data-* attributes to store the value of variables in your HTML output. Scripts, including custom elements, can then read these attributes using an element’s dataset property once your HTML loads in the browser.
Here's an example:
---
const { message = 'Welcome, world!' } = Astro.props;
---
<astro-greet data-message={message}>
<button>Say hi!</button>
</astro-greet>
(Source: Astro Documentation (https://docs.astro.build/en/guides/client-side-scripts#pass-frontmatter-variables-to-scripts))
In your case, you might need to adjust your approach to ensure that the localizePath function runs on the server-side, or find a way to pass the data from the client-side script to your HTML.
Note: you can ask me a follow up question by @ mentioning me again :speech_balloon: