@surma you told us some day that #html can contain multiple same attributes. But is this also possible for `id` or `class`?
I'm currently researching a bit (for #hsml) about this topic and some tools like JSFiddle fails with duplicate `id` not allowed (as same as for `class`).
feat: support id by Shinigami92 · Pull Request #5 · Shinigami92/hsml

A pug-inspired HTML preprocessor. Contribute to Shinigami92/hsml development by creating an account on GitHub.

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@Shini92 Technically it's not valid HTML If you have the same attribute multiple times. But the parsing spec accepts it anyway and — IIRC — the last attribute value wins.

@surma Ah okay, good to know 👍
In this case I think I will just add a compile flag later on if requested and fill fail by default on duplicate `id`/attribute.
Also I will merge class literals with normal classes.

#hsml