Stringtemplate template arguments always evaluated to a string - antlr

Question

I'm using Antlr 4 RC1 (the complete jar) to parse a grammar, build a custom ast, and generate code from that AST with stringtemplate4 (I use the stringtemplate classes in the antlr jar).
Inside a template I call another template with a list of beans e.g.
<subtemplate(myListArg=parm.listOfBeans)>
then inside subtemplate I get a list of Strings (each string is one of the beans evaluated to a String). But what I need is the list of java beans (e.g. simple java object with properties) because I want to process the properties of the beans and not the value of the beans, e.g.
<subtemplate(myListArg)> ::= <<
<myListArg: {x | {... <x.someProperty> ...}>
>>
Looks to me like parameters of a template are always evaluated to strings. Is that the intended behaviour? If yes what should else should I write?

Answer 1

StringTemplate 4 does not render the members of an array or List to strings while calling a subtemplate, as verified by the following. Edit: Despite claims to the contrary in the comments on this post, I reiterate that ST4 does not render the members of an array or List to strings while calling a subtemplate. The element types stored in the array or list make no difference.
start(class) ::= <<
<fields(class.fields)>
>>
fields(fieldsArray) ::= <<
<fieldsArray:{field | <field.name>}; separator="\n">
>>
If you create an instance of the start template and pass Integer.class for the class parameter, you get the following output:
MIN_VALUE
MAX_VALUE
TYPE
SIZE
One of the following must be occurring in your application:
myListArg is not actually a list of strings (i.e. you are getting unexpected output, but not for the reason listed here)
You have a ModelAdaptor registered for the type of parm which is returning a list of strings for the property listOfBeans
The type of parm has a getListOfBeans method which returns a list of strings
Item (3) does not hold, and the type of parm has a listOfBeans field which is a list of strings
Edit: Regarding the question of lists vs. arrays, I performed the unit test above with passing new Clazz(Integer.class) instead of just Integer.class to the start template:
private static class Clazz {
private final Class<?> clazz;
public Clazz(Class<?> clazz) {
this.clazz = clazz;
}
public List<Field> getFields() {
return Arrays.asList(clazz.getFields());
}
}