@Override
  public ConfigExpression<I, O> simplifyOnce() {
    var result = tryStaticEvaluate();
    if (result.isSuccess()) {
      return ConfigExpression.constOf(result.get());
    } else if (descriptor.containsVariable(scriptText.strip())) {
      return ConfigExpression.variable(ConfigExpression.signature(descriptor, returnType), scriptText.strip());
    }
    return this;
  }
Attempts to parse and evaluate this script in an environment with no variables.
<p>
If this returns {@link Try.Success} then it means this script will always return the same constant value and we can
avoid evaluating it at runtime.
planetiler-custommap/src/main/java/com/onthegomap/planetiler/custommap/expression/ConfigExpressionScript.java