Nesting one template inside another with StringTemplate 4

Question

I am having problem understanding how to nest another template inside another. For example, I have 3 templates: application.stg, wrapper.stg and core.stg.

core.stg:

page(data1, data2) ::= <<
  <h1>$data1$</h1>
  <h1>$data2$</h1>
>>

wrapper.stg:

page(data3, data4) ::= <<
  <h1>$data3$</h1>

  <!----- CORE.STG GOES HERE ------->

  <h1>$data4$</h1>
>>

application.stg:

   page(data7, data8) ::= <<
      <h1>$data7$</h1>

      <!----- WRAPPER.STG GOES HERE ------->

      <h1>$data8$</h1>
    >>

The documentation seems to hint that this is possible (Conditional Subtemplate section), but sorry, I could not figure out the syntax at all. Please help me out.

Answer 1

You can create a whole file with every template and make sure you set the .stg extension to it. Then create a TemplateGroupFile object and set the properties data7 and data8 and tell it to start in the application template.

core(data1, data2) ::= <<
  <h1>$data1$</h1>
  <h1>$data2$</h1>
>>

wrapper(data3, data4) ::= <<
  <h1>$data3$</h1>
  core(data3,data4)
  <h1>$data4$</h1>
>>

application(data7, data8) ::= <<
  <h1>$data7$</h1>
  wrapper(data7,data8)
  <h1>$data8$</h1>
>>

This is the C# code

TemplateGroupFile grp = new TemplateGroupFile(Template);
Template page_tpl = grp.GetInstanceOf(GroupName);
GroupName = "application";
page_tpl.Add("data7", yourData);
page_tpl.Add("data8", moreOfYourData);
File.WriteAllText(Path.Combine(dir, Path.GetFileName(outputFile)), page_tpl.Render());