in src/main/java/org/apache/sling/scripting/sightly/java/compiler/impl/ExpressionTranslator.java [124:131]
public void visit(UnaryOperation unaryOperation) {
UnaryOperator operator = unaryOperation.getOperator();
ExpressionNode operand = unaryOperation.getTarget();
UnaryOpGen unaryOpGen = Operators.generatorFor(operator);
source.startExpression();
unaryOpGen.generate(source, this, typeInfo.getTyped(operand));
source.endExpression();
}