1. Strings are indexed by char, at least if you use `[]` or `items()` on
them. Nim has a "byte" type but it is not used frequently and just an alias for
"uint8". It also has int8, uint8 and char which are all "a byte".
2. `items()` is not a function so you can't call it like one. It is an
iterator. Look up how it is implemented for strings:
[here](https://github.com/nim-lang/Nim/blob/f795941f1fc2ee704b84016a869a474df2d5adee/lib/system.nim#L3431-L3438)
and in general
[here](https://github.com/nim-lang/Nim/blob/f795941f1fc2ee704b84016a869a474df2d5adee/lib/system.nim#L1964-L1969)
3. `toSeq()` is not a function either but a template which will generate just
the code one would write manually. I think you should really look up how it is
implemented:
[here](https://github.com/nim-lang/Nim/blob/f795941f1fc2ee704b84016a869a474df2d5adee/lib/pure/collections/sequtils.nim#L459-L483)
4. I really mean you to look at the linked code in 2 and 3. That is "Nim" and
how it works. Thats important! It also hopefully makes some stuff clear when
you think about point 5.
5. All "systems library" code is literally used when you compile. Same as the
code you have written by yourself. There is no "better (faster) system library
implementation" as in Python. Well, besides that those may sometimes have some
clever tricks ... or not.
6. Using constructs like the ones in Python may be as slow as they are in
Python! Pythons implementation of some language constructs are just what Nim
uses too. It is just native code working with garbage collected memory in a
mostly naive fashion. So you may just get equivalent speeds. The real deal is
to really use Nim.
7. IMHO: Using Nim "counterfeit" as Python will bite you pretty soon. Nim is
not Python and never will be. Learning Nim after having used Python is a good
thing though.
