FromStr for floats (#214)

* FromStr for floats

Signed-off-by: Mihai Budiu <[email protected]>

* Address review comments

Signed-off-by: Mihai Budiu <[email protected]>

Signed-off-by: Mihai Budiu <[email protected]>

Author: Mihai Budiu

src/algebra/floats.rs

@@ -4,7 +4,9 @@ use size_of::SizeOf;
 use std::{
     fmt::{self, Debug, Display},
     iter::{Product, Sum},
+    num::ParseFloatError,
     ops::{Add, AddAssign, Div, DivAssign, Mul, MulAssign, Neg, Sub, SubAssign},
+    str::FromStr,
 };
 
 #[cfg(feature = "with-serde")]
@@ -361,6 +363,15 @@ macro_rules! float {
                     Display::fmt(&self.0.0, f)
                 }
             }
+
+            impl FromStr for $outer {
+                type Err = ParseFloatError;
+
+                #[inline]
+                fn from_str(src: &str) -> Result<$outer, ParseFloatError> {
+                    $inner::from_str(src).map($outer::new)
+                }
+            }
         )*
     };
 }
@@ -384,3 +395,10 @@ impl From<F64> for F32 {
         Self::new(float.into_inner() as f32)
     }
 }
+
+#[test]
+fn fromstr() {
+    assert_eq!(Ok(F32::new(10.0)), F32::from_str("10"));
+    assert_eq!(Ok(F64::new(-10.0)), F64::from_str("-10"));
+    assert!(F32::from_str("what").is_err());
+}