Remember to return the generated value, not the upper bound :P

Author: amatgil

src/algorithm/dyadic/mod.rs

@@ -2175,9 +2175,9 @@ impl Value {
                 let i = RNG.with_borrow_mut(|rng| {
                     let upper = len.next_power_of_two();
                     loop {
-                        let r = rng.next_u64() as usize;
-                        if r % upper < len {
-                            break len;
+                        let r = rng.next_u64() as usize % upper;
+                        if r < len {
+                            break r;
                         }
                     }
                 });

src/algorithm/monadic/sort.rs

@@ -233,7 +233,15 @@ impl<T: ArrayValue> Array<T> {
             let row_len = self.row_len();
             let slice = self.data.as_mut_slice();
             for i in (1..row_count).rev() {
-                let j = rng.gen_range(0..=i);
+                let j = {
+                    let upper = i.next_power_of_two();
+                    loop {
+                        let r = rng.next_u64() as usize % upper;
+                        if r <= i {
+                            break r;
+                        }
+                    }
+                };
                 if i == j {
                     continue;
                 }

src/run_prim.rs

@@ -1788,7 +1788,8 @@ fn undo_regex(env: &mut Uiua) -> UiuaResult {
 }
 
 thread_local! {
-    pub(crate) static RNG: RefCell<Xoshiro256Plus> = RefCell::new(Xoshiro256Plus::from_seed(transmute(SystemTime::now().saturating_duration_since(UNIX_EPOCH).as_micros())));
+    pub(crate) static RNG: RefCell<Xoshiro256Plus> = RefCell::new(Xoshiro256Plus::seed_from_u64(
+        SystemTime::now().duration_since(UNIX_EPOCH).map(|t|t.as_micros()).unwrap_or(42) as u64));
 }
 
 /// Generate a random number, equivalent to [`Primitive::Rand`]