Missing template features and syntaxes

[NullVoxPopuli]

tl;dr: this is a checklist / meta-issue

This is kind of a meta issue tracking everything the community (and myself) wants to add to templates, and without these features, it feels like once you get to a big enough project, you feel pretty limited / have tied hands, if that makes sense. We can expand on the need, use cases, ergonomics, etc in separate issues.

In no particular order,

Features

• [ ] Primitives
  • [ ] https://github.com/emberjs/rfcs/issues/623
  • [x] https://github.com/emberjs/rfcs/issues/473
  • [ ] array literals (arrays without array helper)
    • [x] half-way there: built-in: https://github.com/emberjs/rfcs/pull/1000
  • [ ] object / hash literals (objects without hash helper)
    • [x] half-way there: built-in: https://github.com/emberjs/rfcs/pull/999
• [ ] Built-in helpers
  • https://github.com/emberjs/rfcs/issues/714
  • [x] https://github.com/emberjs/rfcs/pull/562
    • [ ] needs implementation
  • [x] https://github.com/emberjs/rfcs/pull/561
    • [ ] needs implementation
  • [x] https://github.com/emberjs/rfcs/pull/560
    • [ ] needs implementation
  • [x] https://github.com/emberjs/rfcs/pull/391
    • [ ] needs implementation
  • [x] https://github.com/emberjs/rfcs/pull/999
    • [ ] needs implementation
  • [x] https://github.com/emberjs/rfcs/pull/1000
    • [ ] needs implementation
• [ ] Destructuring
  • https://github.com/emberjs/rfcs/issues/553
  • https://github.com/emberjs/rfcs/issues/602
• [ ] Currying Components
  • [ ] attributes - https://github.com/emberjs/rfcs/issues/497
  • [ ] modifiers
  • [ ] blocks
• [ ] https://github.com/emberjs/rfcs/issues/805
• [ ] https://github.com/emberjs/rfcs/pull/593
  • [ ] https://github.com/emberjs/rfcs/issues/184
• [ ] Named blocks as arguments
  • https://github.com/emberjs/rfcs/issues/791
  • https://github.com/emberjs/rfcs/issues/735
  • https://github.com/emberjs/rfcs/pull/460#issuecomment-902961346
• [ ] Context / component-tree scoped-services
  • https://github.com/emberjs/rfcs/issues/775
  • [ ] Error Boundaries
    • [ ] https://github.com/emberjs/rfcs/issues/513
    • [ ] https://github.com/emberjs/rfcs/issues/518
• [ ] https://github.com/emberjs/rfcs/issues/517
• [ ] https://github.com/emberjs/rfcs/pull/695

Consistency

• [ ] https://github.com/emberjs/rfcs/issues/1100
• [x] https://github.com/emberjs/rfcs/issues/803
• [ ] https://github.com/emberjs/ember.js/pull/20017
  • [ ] Needs generic solution so that we follow JS semantics
• [ ] https://github.com/emberjs/rfcs/issues/917

[machty]

Thank you for compiling and maintaining this <3