Sure, maplit's hashmap! is just a convenience macro, but then so is vec!. Hashtables are a pretty fundamental data type and they deserve to be easy to write constant initializers for, just like vectors.
'const fn' seems like a red herring -- I don't want to write const functions, because I don't want to write code to initialize data structures at all. I want to write representations of data structures...
Sure, I think it's a useful crate. But it's certainly not "Need[ed] ... to have a global constant-initialized hash table" that's all.
const fn isn't a red herring; you won't be writing const fns, you'll be using them to do the actual initialization. If maplit would use them internally, for example.
'const fn' seems like a red herring -- I don't want to write const functions, because I don't want to write code to initialize data structures at all. I want to write representations of data structures...