How does s% reference the title attribute inside the Helmet component?

Question

Could you help me understand how %s is referencing the component's title attribute inside the component in the gatsby starter theme?

Line 19:

titleTemplate={`%s | ${data.site.siteMetadata.title}`}

user_2116041 · Answer

$s is inferred from the "title" prop of your component.

Here is a link to the relevant source code:

user_1932552 · Answer

The pattern %s is used to be replaced for string:

const str = 'world';
console.log('Hello %s!', str);