docs: RawCode description of rust codec

src/rust_ffi/src/codec/raw_code.rs

@@ -2,6 +2,7 @@ use std::fmt;
 use super::ffi as codec_ffi;
 use super::{ShortCode, CommonCode};
 
+#[derive(Debug)]
 pub struct RawCode {
     code: u64
 }
@@ -15,17 +16,23 @@ impl PartialEq for RawCode {
 }
 
 impl fmt::Display for RawCode {
+    /// Output RawCode for debug.
+    ///   Format:  XXXXXXXXXXXXXXX (length 15)
+    ///   Example: 603EDF5CAFFF5E2
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{:015X}", self.code)
     }
 }
 
 impl RawCode {
+    /// Check if the input `u64` value is a valid raw code.
     #[inline]
     pub(crate) fn check(raw_code: u64) -> bool {
         codec_ffi::raw_code_check(raw_code)
     }
 
+    /// Creates an unchecked raw code, which is not safe and is only used
+    /// during encoding conversion (to ensure no errors).
     #[inline]
     pub(crate) fn new(raw_code: u64) -> RawCode {
         RawCode {
@@ -33,6 +40,16 @@ impl RawCode {
         }
     }
 
+    /// Create raw code from raw `u64`, and will be checked for validity.
+    /// # Example
+    /// ```
+    /// use klotski_ffi::RawCode;
+    ///
+    /// match RawCode::from(0x0603_EDF5_CAFF_F5E2) {
+    ///     Ok(code) => println!("result: {}", code),
+    ///     Err(err) => println!("error: {}", err),
+    /// }
+    /// ```
     pub fn from(raw_code: u64) -> Result<RawCode, &'static str> {
         match RawCode::check(raw_code) {
             true => Ok(RawCode {
@@ -41,25 +58,62 @@ impl RawCode {
             _ => Err("invalid raw code"),
         }
     }
+}
 
+impl RawCode {
     // TODO: from ShortCode (u32 / String / CommonCode)
     // TODO: from CommonCode (u64 / String / CommonCode)
+}
+
+impl RawCode {
+    /// Return the original `u64` type raw code value.
+    /// # Example
+    /// ```
+    /// use klotski_ffi::RawCode;
+    ///
+    /// let code = RawCode::from(0x0603_EDF5_CAFF_F5E2).expect("invalid raw code");
+    /// println!("original: {}", code.unwrap());
+    /// ```
+    #[inline]
+    pub fn unwrap(&self) -> u64 {
+        self.code
+    }
 
+    /// Convert RawCode to ShortCode type, note that it will take a long time if there
+    /// is no warm-up index.
+    /// # Example
+    /// ```
+    /// use klotski_ffi::RawCode;
+    ///
+    /// let raw_code = RawCode::from(0x0603_EDF5_CAFF_F5E2).unwrap();
+    /// let short_code = raw_code.to_short_code();
+    /// println!("{} => {}", raw_code, short_code);
+    /// ```
+    #[inline]
     pub fn to_short_code(&self) -> ShortCode {
         ShortCode::new(
             codec_ffi::raw_code_to_short_code_unsafe(self.code)
         )
     }
 
+    /// Convert RawCode to CommonCode type.
+    /// # Example
+    /// ```
+    /// use klotski_ffi::RawCode;
+    ///
+    /// let raw_code = RawCode::from(0x0603_EDF5_CAFF_F5E2).unwrap();
+    /// let common_code = raw_code.to_common_code();
+    /// println!("{} => {}", raw_code, common_code);
+    /// ```
+    #[inline]
     pub fn to_common_code(&self) -> CommonCode {
         CommonCode::new(
             codec_ffi::raw_code_to_common_code_unsafe(self.code)
         )
     }
+}
 
-    pub fn unwrap(&self) -> u64 {
-        self.code
-    }
+impl RawCode {
 
     // TODO: mirror function