From f6fbf001f5e27f3bff1eacc68ca9c6cac9ee7853 Mon Sep 17 00:00:00 2001
From: Matt Bilker <me@mbilker.us>
Date: Wed, 12 Dec 2018 07:57:17 +0000
Subject: [PATCH] value: add TryFrom implementations to get inner type from
 value

---
 Cargo.toml       |  1 +
 src/lib.rs       |  1 +
 src/value/mod.rs | 14 ++++++++++++++
 3 files changed, 16 insertions(+)

diff --git a/Cargo.toml b/Cargo.toml
index 49c66e1..b73472f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -23,3 +23,4 @@ serde_derive = { version = "1.0.79", optional = true }
 
 [features]
 serde-1 = ["serde", "serde_bytes", "serde_derive", "indexmap/serde-1"]
+try_from = []
diff --git a/src/lib.rs b/src/lib.rs
index 7a2b5c1..e40d718 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,4 +1,5 @@
 #![cfg_attr(test, feature(test))]
+#![cfg_attr(feature = "try_from", feature(try_from))]
 
 extern crate byteorder;
 extern crate bytes;
diff --git a/src/value/mod.rs b/src/value/mod.rs
index d500fca..797b9d0 100644
--- a/src/value/mod.rs
+++ b/src/value/mod.rs
@@ -1,3 +1,5 @@
+#[cfg(feature = "try_from")]
+use std::convert::TryFrom;
 use std::fmt;
 use std::net::Ipv4Addr;
 use std::str::FromStr;
@@ -412,6 +414,18 @@ macro_rules! construct_types {
           Value::$konst(value)
         }
       }
+
+      #[cfg(feature = "try_from")]
+      impl TryFrom<Value> for $($value_type)* {
+        type Error = KbinError;
+
+        fn try_from(value: Value) -> Result<Self, Self::Error> {
+          match value {
+            Value::$konst(v) => Ok(v),
+            value => Err(KbinErrorKind::ValueTypeMismatch(StandardType::$konst, value).into()),
+          }
+        }
+      }
     )+
 
     impl Value {