Add Radix structure to convert number to any radix up to 36.

src/structs.rs

@@ -1,4 +1,5 @@
 use crate::password::{Comment, Name, PasswordRef};
+use std::fmt;
 
 #[derive(thiserror::Error, Debug, PartialEq)]
 pub enum LKErr<'a> {
@@ -57,3 +58,53 @@ impl std::fmt::Display for Mode {
         )
     }
 }
+
+pub struct Radix {
+    x: i32,
+    radix: u32,
+}
+
+impl Radix {
+    pub fn new(x: i32, radix: u32) -> Result<Self, &'static str> {
+        if radix < 2 || radix > 36 {
+            Err("Unnsupported radix")
+        } else {
+            Ok(Self { x, radix })
+        }
+    }
+}
+
+impl fmt::Display for Radix {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let mut x = self.x;
+        // Good for binary formatting of `u128`s
+        let mut result = ['\0'; 128];
+        let mut used = 0;
+        let negative = x < 0;
+        if negative {
+            x*=-1;
+        }
+        let mut x = x as u32;
+        loop {
+            let m = x % self.radix;
+            x /= self.radix;
+
+            result[used] = std::char::from_digit(m, self.radix).unwrap();
+            used += 1;
+
+            if x == 0 {
+                break;
+            }
+        }
+
+        if negative {
+            write!(f, "-")?;
+        }
+
+        for c in result[..used].iter().rev() {
+            write!(f, "{}", c)?;
+        }
+
+        Ok(())
+    }
+}