Having the following definition:

leaf semantics {
type uint16;
}

results in the following builder:

public CommunitiesBuilder setSemantics(Integer value) {

this._semantics = value;
return this;
}

e.g. any integer is allowed, which is obviously wrong, but the change is only ever detected if we attempt to put that field back into an uint16, making the source of the trouble hard to detect. The builder should enforce the range, making the offender fail.