Interface Expression<T>

if (value1 < value2) {
   return "rgba(255, 55, 55, 0.5)";
else {
   return "rgba(55, 255, 55, 0.5)";
}

can be converted to an expression:

var _ = ExpressionFactory;
var expression = _.ifThenElse(_.lt(_.number(value1), _.number(value2)),
                              _.color("rgba(255, 55, 55, 0.5)"),
                              _.color("rgba(55, 255, 55, 0.5)"));

It is not possible to create an Expression directly. Use the ExpressionFactory instead.

since

2017.0