dap4/d4core/src/main/java/dap4/core/ce/CEConstraint.java
protected void computegroups()
    {
        // 1. variables
        for(int i = 0; i < variables.size(); i++) {
            DapVariable var = variables.get(i);
            List<DapGroup> path = var.getGroupPath();
            for(DapGroup group : path) {
                if(!this.groups.contains(group))
                    this.groups.add(group);
            }
        }
        // 2. Dimensions
        for(DapDimension dim : this.dimrefs) {
            if(!dim.isShared())
                continue;
            List<DapGroup> path = dim.getGroupPath();
            for(DapGroup group : path) {
                if(!this.groups.contains(group))
                    this.groups.add(group);
            }
        }
        // 2. enumerations
        for(DapEnumeration en : this.enums) {
            List<DapGroup> path = en.getGroupPath();
            for(DapGroup group : path) {
                if(!this.groups.contains(group))
                    this.groups.add(group);
            }
        }
    }
protected void computegroups()
    {
        // 1. variables
        for(int i = 0; i < variables.size(); i++) {
            DapVariable var = variables.get(i);
            List<DapGroup> path = var.getGroupPath();
            for(DapGroup group : path) {
                if(!this.groups.contains(group))
                    this.groups.add(group);
            }
        }
        // 2. Dimensions
        for(DapDimension dim : this.dimrefs) {
            if(!dim.isShared())
                continue;
            List<DapGroup> path = dim.getGroupPath();
            for(DapGroup group : path) {
                if(!this.groups.contains(group))
                    this.groups.add(group);
            }
        }
        // 2. enumerations
        for(DapEnumeration en : this.enums) {
            List<DapGroup> path = en.getGroupPath();
            for(DapGroup group : path) {
                if(!this.groups.contains(group))
                    this.groups.add(group);
            }
        }
    }
Walk all the included declarations
and accumulate the set of referenced groups