allow inlining (this did not provide a statistically significant performance boost - oh well)

src/position.rs

@@ -7,6 +7,7 @@ pub struct Position {
 }
 
 impl Position {
+    #[inline]
     pub(crate) fn from(string: String) -> Result<Position, &'static dyn Error> {
         // e.g. "2,5"
         let xy: Vec<&str> = string.split(',').collect();