Predefined definitions in Xtext script

Question

I have the following Xtext grammar:

grammar org.xtext.example.mydsl.MyDsl with org.eclipse.xtext.common.Terminals

generate myDsl "http://www.xtext.org/example/mydsl/MyDsl"

Model:
    defines+=Define*
    usages+=Usage*
;

Define:
    'define' name=ID
;

Usage:
    'usage' name=[Define]
;

And user's my.mydsl works well:

define first

usage first

Now, I would like to separate definitions from usage. Specifically, the requirement is to put one set of definitions into file called 'defs1.mydsl' and another set of (different) definitions into file called 'defs2.mydsl'. The intention is to provide them as read only definitions and make them be a part of Eclipse Xtext plugin.

A user editable file would contain 'use' and 'usage' directives only:

use "defs2.mydsl"

usage second

Would you please describe the steps I should follow to implement this?

Additional question – may I limit user to use 'use' and 'usage' directives only?

Thank you!

Answer 1

克里斯蒂安在Eclipse社区论坛上回答了这个问题