elna/TODO

# Compiler

- Separate headers and sources for the compiler, shell and tests.
- Make writing ELF independent from the code generation.
- Argument parsing.
- Whitespaces are checked twice, in the source class and by lexing.
- Catch exceptions thrown by the argument parser and print them normally.
- Division.
- Expressions contain one or more terms. Currently it parses another expression on the right side.
- Multiple factors.
- Put riscv code into the backend namespace.
- Rename riscv backend structs to be snake case.
- Make reference and Target be nested types of the visitor.
- Rename visitors to snake case.
- The backend visitor seems to generate code before the prologue.

# Shell
- Persist the history.
- Replace hard coded ANSI codes with constants or functions.

## Completion

- Configure fzf to show only the current directory files
- Support multiple selections for insertion in fzf.
- Don't hardcode fzf binary path.
- Send the word under the cursor to fzf as initial input.
- Home directory expansion.
- Show files in the PATH if starting at the beginning of the prompt

## Appearance

- Add a bar with additional information under the prompt (edit_bar), like the hostname.
- Show current time in the prompt.