behaviour consistence between `first` and `last`?

[minghu6]

Env: hy 1.0a1+17.g69a23261

I found:
(first []) returns None,
but (last []) just raise IndexError

[allison-casey]

Hy will be removing builtin methods that are duplicates of methods in more dedicated libraries like Toolz or Funcy for just this reason. If you're looking for implementations of common methods like this with more consistent syntax and performance profiles it's recommended to migrate your code to import from those libraries instead. Part of this migration was already done in #2042 (which removed first and last among others) which will be available in hy 1.0a2.