marwood 0.3.1

Scheme R5RS Virtual Machine
Documentation 
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use std::fmt::Formatter;

const ALARM: u32 = 0x7;
const BACKSPACE: u32 = 0x8;
const DELETE: u32 = 0x7f;
const ESCAPE: u32 = 0x01b;
const NULL: u32 = 0x0;
const RETURN: u32 = 0xd;
const TAB: u32 = 0x9;

pub fn named_to_char(text: &str) -> Option<char> {
    match text {
        "alarm" => Some(char::from_u32(ALARM).unwrap()),
        "backspace" => Some(char::from_u32(BACKSPACE).unwrap()),
        "delete" => Some(char::from_u32(DELETE)).unwrap(),
        "escape" => Some(char::from_u32(ESCAPE)).unwrap(),
        "null" => Some(char::from_u32(NULL)).unwrap(),
        "return" => Some(char::from_u32(RETURN)).unwrap(),
        "tab" => Some(char::from_u32(TAB)).unwrap(),
        "space" => Some(' '),
        "newline" => Some('\n'),
        _ => None,
    }
}

pub fn write_escaped_char(c: char, f: &mut Formatter<'_>) -> std::fmt::Result {
    match c {
        ' ' => write!(f, "#\\space"),
        '\n' => write!(f, "#\\newline"),
        c => match c as u32 {
            ALARM => write!(f, "#\\alarm"),
            BACKSPACE => write!(f, "#\\backspace"),
            DELETE => write!(f, "#\\delete"),
            ESCAPE => write!(f, "#\\escape"),
            NULL => write!(f, "#\\null"),
            RETURN => write!(f, "#\\return"),
            TAB => write!(f, "#\\tab"),
            _ => write!(f, "#\\{}", c),
        },
    }
}