From c7b252ca9d2aafc8a50d1e16f37bd2c889dbd462 Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonyg@leastfixedpoint.com>
Date: Sat, 3 Jul 2021 08:59:22 +0200
Subject: [PATCH] More TryFrom<&SignedInteger> implementations

---
 .../preserves/src/value/signed_integer.rs     | 28 +++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/implementations/rust/preserves/src/value/signed_integer.rs b/implementations/rust/preserves/src/value/signed_integer.rs
index 4d38dd7..7dde714 100644
--- a/implementations/rust/preserves/src/value/signed_integer.rs
+++ b/implementations/rust/preserves/src/value/signed_integer.rs
@@ -144,3 +144,31 @@ impl<'a> From<&'a SignedInteger> for BigInt {
         }
     }
 }
+
+impl TryFrom<&SignedInteger> for i64 {
+    type Error = ();
+    fn try_from(v: &SignedInteger) -> Result<Self, Self::Error> {
+        i128::try_from(v)?.try_into().map_err(|_| ())
+    }
+}
+
+impl TryFrom<&SignedInteger> for u64 {
+    type Error = ();
+    fn try_from(v: &SignedInteger) -> Result<Self, Self::Error> {
+        u128::try_from(v)?.try_into().map_err(|_| ())
+    }
+}
+
+impl TryFrom<&SignedInteger> for isize {
+    type Error = ();
+    fn try_from(v: &SignedInteger) -> Result<Self, Self::Error> {
+        i128::try_from(v)?.try_into().map_err(|_| ())
+    }
+}
+
+impl TryFrom<&SignedInteger> for usize {
+    type Error = ();
+    fn try_from(v: &SignedInteger) -> Result<Self, Self::Error> {
+        u128::try_from(v)?.try_into().map_err(|_| ())
+    }
+}