diff --git a/.github/workflows/continuous-integration.yml b/.github/workflows/continuous-integration.yml
index d82bd19..7867625 100644
--- a/.github/workflows/continuous-integration.yml
+++ b/.github/workflows/continuous-integration.yml
@@ -41,7 +41,7 @@ jobs:
       matrix:
         os: [macOS-latest, ubuntu-latest, windows-latest]
         toolchain:
-          - 1.65.0 # Minimum.
+          - 1.70.0 # Minimum.
           - stable
           - beta
     steps:
diff --git a/Cargo.toml b/Cargo.toml
index 0a221c3..b48efa8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,6 +2,7 @@
 name = "decorum"
 version = "0.3.1"
 edition = "2021"
+rust-version = "1.70.0"
 license = "MIT"
 readme = "README.md"
 authors = ["Sean Olson <olson.sean.k@gmail.com>"]
diff --git a/src/expression.rs b/src/expression.rs
index 0815ed7..43161a7 100644
--- a/src/expression.rs
+++ b/src/expression.rs
@@ -532,12 +532,11 @@ where
     const NEG_INFINITY: Self = Defined(InfinityEncoding::NEG_INFINITY);
 
     fn is_infinite(self) -> bool {
-        self.defined()
-            .map_or(false, |defined| defined.is_infinite())
+        self.defined().is_some_and(InfinityEncoding::is_infinite)
     }
 
     fn is_finite(self) -> bool {
-        self.defined().map_or(false, |defined| defined.is_finite())
+        self.defined().is_some_and(InfinityEncoding::is_finite)
     }
 }
 
@@ -587,7 +586,7 @@ where
         self.as_ref()
             .defined()
             .zip(other.as_ref().defined())
-            .map_or(false, |(left, right)| left.eq(right))
+            .is_some_and(|(left, right)| left.eq(right))
     }
 }
 
@@ -647,11 +646,11 @@ where
     const LOG10_E: Self = Defined(UnaryRealFunction::LOG10_E);
 
     fn is_zero(self) -> bool {
-        self.defined().map_or(false, |defined| defined.is_zero())
+        self.defined().is_some_and(UnaryRealFunction::is_zero)
     }
 
     fn is_one(self) -> bool {
-        self.defined().map_or(false, |defined| defined.is_one())
+        self.defined().is_some_and(UnaryRealFunction::is_one)
     }
 
     fn sign(self) -> Sign {