Is your list things that you wish were in the language, or things you wish the implementations had?
- Heredocs: implementation missing.
- Shaped arrays and hashes are specced, but haven't been implemented by anybody yet. So while it's mostly a question of the implementation, the spec will need to be tuned to respond to feedback from the compiler writers
- Speed: an implementation thing, although of course language design decisions influence it too
- Mutable grammars: needs work on both fronts.
- polishing: everything (compilers, specs, docs, module installers, ...)
Could you briefly explain what "shaped arrays" are? I've never heard that term, and Synopsis 9 is pretty dense.
Arrays where you can exactly declare the dimensionality, index ranges and types. For example you could declare a two-dimensional array where both indexes run from 0 to 2 and and only store Num objects -- the perfect base for Matrix arithmetics.
Those predeclarations allow both type checking and much more compact storage.