From 6ee6140ba8f08cd174a43cc45ef8c0b4af8747c9 Mon Sep 17 00:00:00 2001
From: Marrub <marrub.xz@gmail.com>
Date: Mon, 18 Mar 2019 12:07:44 -0400
Subject: [PATCH] simplify OptU16 API

---
 source/durandal/bin.rs | 85 ++++++++++++++++++++++++------------------
 1 file changed, 48 insertions(+), 37 deletions(-)

diff --git a/source/durandal/bin.rs b/source/durandal/bin.rs
index f4c8e60..0be9177 100644
--- a/source/durandal/bin.rs
+++ b/source/durandal/bin.rs
@@ -49,7 +49,7 @@ macro_rules! _durandal_read_impl {
    };
    ($e:ident $b:expr; $nam:ident OptU16 $n:expr) => {
       _durandal_read_impl!($e $b; $nam u16 $n);
-      let $nam = OptU16::from_repr($nam);
+      let $nam = OptU16::from($nam);
    };
    ($e:ident $b:expr; $nam:ident usize u16 $n:expr) => {
       _durandal_read_impl!($e $b; $nam u16 $n);
@@ -114,7 +114,7 @@ macro_rules! _durandal_read_impl {
 ///   - `Unit`: same as `u16`, but the result is passed to
 ///     `fixed::Unit::from_bits`, resulting in a `fixed::Unit` object.
 ///   - `OptU16`: same as `u16`, but the result is passed to
-///     `OptU16::from_repr`, resulting in an `OptU16` object.
+///     `OptU16::from`, resulting in an `OptU16` object.
 ///   - The name of a function, which is passed `&source[place]` as its only
 ///     argument. The function's result has the `?` operator applied to it.
 /// - `opts` may be one of:
@@ -376,6 +376,46 @@ pub fn rd_ofstable<T, F>(b: &[u8],
    Ok(v)
 }
 
+impl From<u16> for OptU16
+{
+   #[inline]
+   fn from(n: u16) -> Self
+   {
+      if n == u16::max_value() {
+         Self(None)
+      } else {
+         Self(NonZeroU16::new(n + 1))
+      }
+   }
+}
+
+impl Into<u16> for OptU16
+{
+   /// Returns the `u16` representation.
+   ///
+   /// # Examples
+   ///
+   /// ```
+   /// use maraiah::durandal::bin::OptU16;
+   ///
+   /// let u16_max = u16::max_value();
+   ///
+   /// // These type annotations are necessary.
+   ///
+   /// assert_eq!(<OptU16 as Into<u16>>::into(OptU16::from(500u16)), 500u16);
+   /// assert_eq!(<OptU16 as Into<u16>>::into(OptU16::from(u16_max)), u16_max);
+   /// assert_eq!(<OptU16 as Into<u16>>::into(OptU16::from(0u16)), 0u16);
+   /// ```
+   #[inline]
+   fn into(self) -> u16
+   {
+      match self.0 {
+         None    => u16::max_value(),
+         Some(n) => n.get() - 1,
+      }
+   }
+}
+
 impl OptU16
 {
    /// Creates an `OptU16` representing `None`.
@@ -385,41 +425,11 @@ impl OptU16
    /// ```
    /// use maraiah::durandal::bin::OptU16;
    ///
-   /// assert_eq!(OptU16::none(), OptU16::from_repr(u16::max_value()));
+   /// assert_eq!(OptU16::none(), OptU16::from(u16::max_value()));
    /// ```
+   #[inline]
    pub const fn none() -> Self {Self(None)}
 
-   /// Creates an `OptU16` from a `u16`.
-   pub fn from_repr(n: u16) -> Self
-   {
-      if n == u16::max_value() {
-         Self(None)
-      } else {
-         Self(NonZeroU16::new(n + 1))
-      }
-   }
-
-   /// Returns the `u16` representation.
-   ///
-   /// # Examples
-   ///
-   /// ```
-   /// use maraiah::durandal::bin::OptU16;
-   ///
-   /// let u16max = u16::max_value();
-   ///
-   /// assert_eq!(OptU16::from_repr(500u16).get_repr(), 500u16);
-   /// assert_eq!(OptU16::from_repr(u16max).get_repr(), u16max);
-   /// assert_eq!(OptU16::from_repr(0u16).get_repr(), 0u16);
-   /// ```
-   pub fn get_repr(self) -> u16
-   {
-      match self.0 {
-         None    => u16::max_value(),
-         Some(n) => n.get() - 1,
-      }
-   }
-
    /// Returns the `Option` representation.
    ///
    /// # Examples
@@ -427,10 +437,11 @@ impl OptU16
    /// ```
    /// use maraiah::durandal::bin::OptU16;
    ///
-   /// assert_eq!(OptU16::from_repr(500u16).get(), Some(500u16));
-   /// assert_eq!(OptU16::from_repr(u16::max_value()).get(), None);
-   /// assert_eq!(OptU16::from_repr(0u16).get(), Some(0u16));
+   /// assert_eq!(OptU16::from(500u16).get(), Some(500u16));
+   /// assert_eq!(OptU16::from(u16::max_value()).get(), None);
+   /// assert_eq!(OptU16::from(0u16).get(), Some(0u16));
    /// ```
+   #[inline]
    pub fn get(self) -> Option<u16>
    {
       match self.0 {