feat: graceful if statement expression error

Author: Eddie

out/artifacts/jungle_jar/jungle.jar

@@ -100,7 +100,11 @@ protected void visit(
             throw new Error("expected if condition/expression");
         }
 
-        getExpressionVisitor().visit(mv, conditionNode, context);
+        try {
+            getExpressionVisitor().visit(mv, conditionNode, context);
+        } catch (Throwable t) {
+            throw new Error("if condition/expression is not resolvable", t);
+        }
         if (!OperandType.INTEGER_OPERATION_TYPES.contains(context.peek())) {
             throw new Error("if condition/expression expected to be within the integer category");
         }

src/main/java/com/jungle/compiler/visitor/IfVisitor.java

@@ -130,7 +130,7 @@ public void visit(
             case OPERATOR_MULTIPLY: mv.visitInsn(operandType.getMultiplyOpcode()); break;
             case OPERATOR_DIVIDE: mv.visitInsn(operandType.getDivideOpcode()); break; // order matters
             case OPERATOR_MODULO: mv.visitInsn(operandType.getModuloOpcode()); break; // order matters
-            default: throw new Error("unhandled binary operator " + ast);
+            default: throw new Error("unhandled operation " + ast);
         }
     }
 }