public spanSetBlock(lfnode lfnode = default, uint popped = default, array <ptr <mspan> > spans = default)
 {
     this.lfnode = lfnode;
     this.popped = popped;
     this.spans  = spans;
 }
 public workbufhdr(lfnode node = default, long nobj = default)
 {
     this.node = node;
     this.nobj = nobj;
 }