additional stream tools

Signed-off-by: Jason Volk <jason@zemos.net>

src/core/utils/bool.rs

@@ -0,0 +1,16 @@
+//! Trait BoolExt
+
+/// Boolean extensions and chain.starters
+pub trait BoolExt {
+	fn or<T, F: FnOnce() -> T>(self, f: F) -> Option<T>;
+
+	fn or_some<T>(self, t: T) -> Option<T>;
+}
+
+impl BoolExt for bool {
+	#[inline]
+	fn or<T, F: FnOnce() -> T>(self, f: F) -> Option<T> { (!self).then(f) }
+
+	#[inline]
+	fn or_some<T>(self, t: T) -> Option<T> { (!self).then_some(t) }
+}