What is this?

Just a tiny "program" that converts a regular number to its Roman numeral representation.

> cargo run 888
   Compiling roman-numerals-rs v0.1.0 (/home/ray/projects/personal/rust/roman-numerals-rs)
    Finished dev [unoptimized + debuginfo] target(s) in 0.38s
     Running `target/debug/roman-numerals-rs 888`
DCCCLXXXVIII

Why is this?

Just programming in Rust for fun.