fix a bug in under sided both

Author: kaikalii

src/compile/invert/under.rs

@@ -430,7 +430,9 @@ under!(BothPat, input, g_sig, inverse, asm, {
     );
     let (f_before, mut f_after) = f.under_inverse(inner_g_sig, inverse, asm)?;
 
-    let balanced = g_sig.args() <= g_sig.outputs() && !(val.is_some() && f.sig == (1, 1));
+    let balanced = g_sig.args()
+        <= g_sig.outputs() + sub.side.as_ref().map_or(0, |sided| sided.n.unwrap_or(1))
+        && !(val.is_some() && f.sig == (1, 1));
     // Make before
     let mut before = val.unwrap_or_default();
     before.push(if !inverse || balanced {

tests/under.ua

@@ -167,10 +167,10 @@
 ⍤⤙≍ 5 ⍜∩(×.)+ 3 4
 ⍤⤙≍ {6 5} [⍜∩°□˜⊙∘ □5 □6]
 ⍤⤙≍ [9 9 5] ⍜⊡(⍜∩×↥∩⌟⊙∘) 2 ↯3 9 ¯1 5
-⍤⤙≍ [3 2] ⍜∩⌞▽◌ [1 0] [1 2] [3 4]
 ⍤⤙≍ 0 ⧻ {⍜(∩(|1 ◌ °img&frab))∩∘ ."site/favicon.ico"}
 ⍤⤙≍ [29 39] [⍜∩⌞+∩×₁₀ 1 2 3]
 ⍤⤙≍ [39 48] [⍜∩⌟+∩×₁₀ 1 2 3]
+⍤⤙≍ [2_13 4_15] ⊟ ⍜⊙∩⌞⊡∩⌞+ 10 1 2_3 4_5
 
 # On
 ⍤⤙≍ [3 5] [⍜⟜×∘ 3 5]