Merge pull request #3 from metasim/feature/try-from

Replaced `From<f64>` with `TryFrom<f64>`
xpe · Aug 13, 2024 · afe404e · afe404e
2 parents 9fd4e8a + bfae1ae
commit afe404e
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Showing 3 changed files with 17 additions and 14 deletions.
diff --git a/src/gen.rs b/src/gen.rs
@@ -114,13 +114,16 @@ fn generate_from_data(data: Data) -> syn::Result<TokenStream> {
             }
         }
 
-        impl From<#f64> for #name {
-            fn from(value: #f64) -> Self {
+        impl TryFrom<#f64> for #name {
+            type Error = Box<dyn std::error::Error + Send + Sync>;
+            fn try_from(value: #f64) -> std::result::Result<Self, Self::Error> {
                 if !(Self::MIN_FLOAT..=Self::MAX_FLOAT).contains(&value) {
-                    panic!("{} is out of range for {}", value, Self::Q_NOTATION);
+                    Err(format!("{} is out of range for {}", value, Self::Q_NOTATION).into())
+                }
+                else {
+                    let n = (value * Self::CONVERSION_FACTOR) as #inner_type;
+                    Ok(Self(n & Self::USED_MASK))
                 }
-                let n = (value * Self::CONVERSION_FACTOR) as #inner_type;
-                Self(n & Self::USED_MASK)
             }
         }
 

diff --git a/src/lib.rs b/src/lib.rs
@@ -35,9 +35,9 @@
 //! ```
 //! # use q_num::define_q_num;
 //! define_q_num!(X, Q6.2);
-//! let a = X::from(13.75);
-//! let b = X::from(-2.25);
-//! let c = X::from(11.5);
+//! let a = X::try_from(13.75).unwrap();
+//! let b = X::try_from(-2.25).unwrap();
+//! let c = X::try_from(11.5).unwrap();
 //! assert_eq!(a + b, c);
 //! ```
 //!

diff --git a/tests/macro.rs b/tests/macro.rs
@@ -21,9 +21,9 @@ fn test_q12p5_constants() {
 #[test]
 fn test_q12p5_add() {
     define_q_num!(X, Q12.5);
-    let x1 = X::from(500.25);
-    let x2 = X::from(-744.75);
-    let x3 = X::from(-244.5);
+    let x1 = X::try_from(500.25).unwrap();
+    let x2 = X::try_from(-744.75).unwrap();
+    let x3 = X::try_from(-244.5).unwrap();
     let b1 = x1.to_bits();
     let b2 = x2.to_bits();
     let b3 = x3.to_bits();
@@ -89,7 +89,7 @@ fn test_q5p3_inner_values() {
     define_q_num!(Q, UQ5.3);
     let mut value = 0.0;
     for byte in 0..0b1111_1111 {
-        let q = Q::from(value);
+        let q = Q::try_from(value).unwrap();
         assert_eq!(q.to_bits(), byte);
         value += 0.125;
     }
@@ -103,7 +103,7 @@ fn test_q4p2_inner_values() {
     define_q_num!(Q, UQ4.2);
     let mut value = 0.0;
     for byte in (0..0b1111_1100).step_by(0b100) {
-        let q = Q::from(value);
+        let q = Q::try_from(value).unwrap();
         assert_eq!(q.to_bits(), byte);
         value += 0.25;
     }
@@ -114,5 +114,5 @@ fn test_q4p2_inner_values() {
 #[should_panic]
 fn test_q4p2_out_of_range() {
     define_q_num!(Q, Q4.2);
-    let _ = Q::from(16.00);
+    let _ = Q::try_from(16.00).unwrap();
 }