diff --git a/src/celpy/evaluation.py b/src/celpy/evaluation.py
index 47caf9b..a955ca6 100644
--- a/src/celpy/evaluation.py
+++ b/src/celpy/evaluation.py
@@ -1322,10 +1322,12 @@ def expr(self, tree: lark.Tree) -> Result:
         elif len(tree.children) == 3:
             # full conditionalor "?" conditionalor ":" expr.
             func = self.functions["_?_:_"]
-            cond_value, left, right = cast(Tuple[Result, Result, Result], self.visit_children(tree))
+            cond_value = self.visit(tree.children[0])
             try:
-                return func(cond_value, left, right)
+                return self.visit(tree.children[1]) if func(cond_value, True, False) else self.visit(tree.children[2])
             except TypeError as ex:
+                left = self.visit(tree.children[1]) if cond_value else '-'
+                right = self.visit(tree.children[2]) if cond_value else '-'
                 self.logger.debug("%s(%s, %s) --> %s", func.__name__, left, right, ex)
                 err = (
                     f"found no matching overload for _?_:_ "
@@ -1341,6 +1343,9 @@ def expr(self, tree: lark.Tree) -> Result:
                 column=tree.meta.column,
             )
 
+    def visit(self, child: Union[str, lark.Tree]):
+        return super().visit(child) if isinstance(child, lark.Tree) else child
+
     @trace
     def conditionalor(self, tree: lark.Tree) -> Result:
         """
diff --git a/type_check/lineprecision.txt b/type_check/lineprecision.txt
index b80b663..236743a 100644
--- a/type_check/lineprecision.txt
+++ b/type_check/lineprecision.txt
@@ -9,3 +9,4 @@ celpy.celtypes     1495      430         17  221    788          39
 celpy.evaluation   2434      824         33  172   1390          15
 xlate                 0        0          0    0      0           0
 xlate.c7n_to_cel   1730      384        105  145   1091           5
+