# Brim
Brim is an optimizing brain* interpreter than nonetheless strives to be very
pleasant and easy to use.
## Features
### Details
Brim uses a wrapping 30000-cell tape, with a single wrapping signed byte in
each cell.
### Debug
If compiled in debug mode, or with the feature flag `debug`, brim will
recognize the character `;`, and will dump several relevant bits of info
(the tape, the tape pointer, and three instructions for context) to
output.
### File I/O
With the `-i | --input` and `-o | --output` flags, brim can read/write to/from
files instead of stdin/stdout.
Regardless of source or destination, all I/O is buffered to provide a fast and
reliable experience (the output is flushed on each newline, and upon exit).
### Optimizations
Brim internally uses a token-based intermediary structure to execute the code.
First, it groups together add, subtract, left, and right instructions to save
needless cycles (as well as discards redundant instructions).
Then, it performs several macro-optimizations to reduce common operations to
a single "instruction". Currently, it recognizes:
- Zeroing a cell (`[-]`)
- Setting a cell to a value (`[-]++++`)
- Moving one cell to another (`[->+<]` / `[>+<-]`)
The token-based structure makes these trivial to recognize, since repeating
instructions have already been collapsed into one.
Finally, it iterates over each bracket (`[`/`]`) and pre-loads its destination,
so executing them requires zero lookup time (it just overrides the IP).
These are all run in a buffered I/O environment, as detailed above.
## Roadmap
Brim isn't finished yet! My hopes for the future include:
- More macro-optimizations
- Heavy micro-optimization of brim itself
- More variations (non-wrapping, signed, varying tape size)
## Contributions
Contributions are always welcome, especially optimizations! Please, before you
create a pull request, run `cargo fmt` and `cargo clippy`.
If you want to implement a new feature, consider gating it behind a feature
flag. This can reduce code size as well as slightly improve runtimes. It isn't
appropriate for all, but it is worth considering.