main.rs

use std::fs;
use std::collections::HashMap;
use serde::Deserialize;
use std::convert::TryFrom;
use std::fmt;

#[derive(Deserialize)]
struct Room {
    name: String,
    description: String,
    connections: HashMap<Dir, String>,
    items: Vec<Item>
}

#[derive(Deserialize)]
struct Item {
    name: String,
    description: String
}

#[derive(Debug, Deserialize, Hash, Eq, PartialEq, Copy, Clone)]
#[serde(try_from = "String")]
enum Dir { North, South, East, West, Northeast, Southeast, Northwest, Southwest, Up, Down }

struct InvalidDirError;
impl fmt::Display for InvalidDirError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        f.write_str("InvalidDirError")
    }
}

impl TryFrom<String> for Dir {
    type Error = InvalidDirError;

    fn try_from(s: String) -> Result<Self, Self::Error> {
        match s.as_str() {
            "North" => Ok(Self::North),
            "South" => Ok(Self::South),
            "East" => Ok(Self::East),
            "West" => Ok(Self::West),
            "Northeast" => Ok(Self::Northeast),
            "Southeast" => Ok(Self::Southeast),
            "Northwest" => Ok(Self::Northwest),
            "Southwest" => Ok(Self::Southwest),
            "Up" => Ok(Self::Up),
            "Down" => Ok(Self::Down),
            _ => Err(InvalidDirError),
        }
    }
}
#[derive(Deserialize)]
struct RoomsFile { rooms: Vec<Room> }

fn main() {
    let rooms = fs::read_to_string("rooms.toml").expect("Failed to read rooms.toml");
    let rooms_file: RoomsFile = toml::from_str(rooms.as_str()).expect("Couldn't parse rooms.toml");
    let rooms: Vec<Room> = rooms_file.rooms;

    for room in rooms {
        println!("{}", room.name);
        println!("{}\n", room.description);
    }
}

rooms.toml

[[rooms]]
name = "Foyer"
description = """The grand foyer of the mansion. A staircase goes up to the
balcony and exits to the east and west lead to the drawing room and dining
room respectively."""
connections.East = "Drawing Room"
connections.West = "Dining Room"
connections.Up = "Balcony"
items = []

[[rooms]]
name = "Dining Room"
description = """An elegant dining room with a table that would seat 10 guests.
A door leads east to the main foyer, and another leads north to the kitchen."""
connections.North = "Kitchen"
connections.East = "Foyer"
items = []

[[rooms]]
name = "Kitchen"
description = """This kitchen is dusty and unused, showing empty spots where
appliances and utensils once stood. An exit to the south leads to the dining room"""
connections.South = "Dining Room"
items = []

[[rooms]]
name = "Drawing Room"
description = """This drawing room once entertained the guests after dinner with
amusements such as its billiard table, piano, and bookshelves. A doorway leads west
to the main foyer."""
connections.West = "Foyer"
items = []

[[rooms]]
name = "Balcony"
description = """From the balcony you can look down on the foyer and its dusty crystal
chandelier. A starcase would let you descend to the foyer."""
connections.Down = "Foyer"
items = []