fix experimental checking in un under

Author: kaikalii

examples/shuffle_music.ua

@@ -1,8 +0,0 @@
-# Plays the `Music` song with a shuffled melody
-&ast⋅(
-  Music
-  ♭↯2
-  ▽1.2
-  ⍜(⤸1 ≡(↘1⧈∘¤¤¯4) ⧈∘¤¤¯64)≡°⍆
-  ÷⟜⧈/+5
-)

src/compile/mod.rs

@@ -2369,19 +2369,20 @@ impl Compiler {
     where
         S: ToString,
     {
+        if !self.allow_experimental() {
+            self.scope.experimental_error = true;
+            self.add_error(span.clone(), message().to_string());
+        }
+    }
+    fn allow_experimental(&self) -> bool {
         let take = self
             .scopes()
             .position(|sc| matches!(sc.kind, ScopeKind::File(_)))
             .map(|i| i + 1)
             .unwrap_or(usize::MAX);
-        if !self
-            .scopes()
+        self.scopes()
             .take(take)
             .any(|sc| sc.experimental || sc.experimental_error)
-        {
-            self.scope.experimental_error = true;
-            self.add_error(span.clone(), message().to_string());
-        }
     }
     fn error(&self, span: impl Into<Span>, message: impl ToString) -> UiuaError {
         UiuaErrorKind::Run {

src/compile/modifier.rs

@@ -846,7 +846,7 @@ impl Compiler {
                     SigNode::new(sig, node)
                 };
                 let span = self.add_span(modified.modifier.span.clone());
-                let un = if self.scope.experimental {
+                let un = if self.allow_experimental() {
                     if f.sig.args == f.sig.outputs {
                         let (f_before, f_after) = f
                             .node

todo.md

@@ -2,7 +2,7 @@
 
 # 0.15
 - Allow unnamed data def outside named module
-- Subscripts `bits`
+- Subscripted `bits`
 - Non-dyadic `backward`
 - 0-output `tuples`
 - Implement some `under` inverses in terms of `un by`, rather than the other way around