From 61975f18f3d2198326b56685922b8aa7cf8377a5 Mon Sep 17 00:00:00 2001
From: multisn8 <contact@multisamplednight.com>
Date: Sat, 30 Apr 2022 22:09:29 +0200
Subject: [PATCH] Add lossy conversion for `NotNan<f64>` to `NotNan<f32>`
 (#109)

---
 src/lib.rs | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/lib.rs b/src/lib.rs
index c797699..f3ac064 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -954,6 +954,18 @@ impl<T: Float + fmt::Display> fmt::Display for NotNan<T> {
     }
 }
 
+impl NotNan<f64> {
+    /// Converts this [`NotNan`]`<`[`f64`]`>` to a [`NotNan`]`<`[`f32`]`>` while giving up on
+    /// precision, [using `roundTiesToEven` as rounding mode, yielding `Infinity` on
+    /// overflow](https://doc.rust-lang.org/reference/expressions/operator-expr.html#semantics).
+    pub fn as_f32(self) -> NotNan<f32> {
+        // This is not destroying invariants, as it is a pure rounding operation. The only two special
+        // cases are where f32 would be overflowing, then the operation yields Infinity, or where
+        // the input is already NaN, in which case the invariant is already broken elsewhere.
+        NotNan(self.0 as f32)
+    }
+}
+
 impl From<NotNan<f32>> for f32 {
     #[inline]
     fn from(value: NotNan<f32>) -> Self {