{{else}} should render a value rather than be a control-flow keyword. about rfcs HOT 5 OPEN

This is a good thing to consider changing, though note that keywords and control structures in most languages are allowed to have their own syntactic forms. I would also suggest that the time to make that change would be in a broader syntactic reform, i.e. a switch to a single-curly-based form that is similar to Svelte's templates:

<template lang='sveltish'>
  {#if condition}
  {:else if otherCondition}
  {:else}
  {/if}
</template>

from rfcs.

+1 for broader reform. Been thinking of proposing this since it actually wouldn't be hard to implement in the parser and could be done initially as an external optional offering. Double curlies don't feel necessary anymore to me.

from rfcs.

I think this is something that Ember has inherited from Handlebars:
https://handlebarsjs.com/guide/builtin-helpers.html#if

I don't know how far Ember templates has deviated from Handlebars, so maybe going further away isn't a problem.

But one thing to consider is that Handlebars tooling (linting, syntax highlighters, etc) mostly work with Ember, which is nice. With a custom template language, Ember would have to maintain that stuff themselves, which is more work.

from rfcs.

That's correct; technically Glimmer templates are still Handlebars templates. They've diverged substantially, but by addition rather than by change overall. The first pass of the parser is the JS Handlebars parser… but then we have to do more work to get to what we have today. That's a real and genuine concern, regardless, especially as regards syntax highlighting.

from rfcs.