Template semantics

A template consist of JSON entities which are evaluated recursively on some input queryset available as $ to SakStig expressions. Initially, the template context @template() is set to the same as $. The output is a queryset.

The template is an object

If the template contains a member named $

• The value of template.$ is evaluated as a SakStig expression to form an input queryset.
• If the template does not contain any other members than $, input is returned and evaluation ends.
• Each input entry is transformed to form a new queryset which is returned.

input entry transform:

• @template is set to a queryset containing only the current input entry.
• A new empty output object is created.
• For each member of the template:
  • member.value is evaluated recursively as a template to form a value queryset.   - If value is the empty queryset, the member is ignored.
  • output[member.name] is set to the first entry in the value queryset.

If the template does not contain a member named $

• A new empty output_object is created
• For each member of the template:   - member.value is evaluated recursively as a template to form a value queryset.   - If value is the empty queryset, the member is ignored.   - output_object[member.name] is set to the first entry in the value queryset.
• output_object is returned as a single member of a queryset.

The template is an array

• Each array member is evaluated recursively as a template.
• All the resulting querysets are concatenated and converted into a JSON array which is returned as a single member of a queryset.

Other values

All other values are returned verbatim as a single member of a queryset.