refactor: remove dead Symbol checks from Modulo

Remove explicit Symbol type checks from Modulo() that are never reached.
The toFloat64() helper already rejects non-numeric types (including Symbol)
with a proper error, so the Symbol-specific error messages in Modulo are
dead code. This makes Modulo consistent with Add, Subtract, Multiply,
Divide, and other operators that rely solely on toFloat64() for type
validation.

1 files changed, 0 insertions, 7 deletions

diff --git a/internal/rpn/operations_arithmetic.go b/internal/rpn/operations_arithmetic.go
index 2df45bd..3215917 100644
--- a/internal/rpn/operations_arithmetic.go
+++ b/internal/rpn/operations_arithmetic.go
@@ -193,13 +193,6 @@ func (o *Operations) Modulo(stack *Stack) error {
 		return err
 	}
 
-	if sym, ok := a.(*Symbol); ok {
-		return fmt.Errorf("symbol %s cannot be used with modulo operator", sym.Name())
-	}
-	if sym, ok := b.(*Symbol); ok {
-		return fmt.Errorf("symbol %s cannot be used with modulo operator", sym.Name())
-	}
-
 	bF, err := toFloat64(b, "%")
 	if err != nil {
 		return err