public XQExpression staticAnalysis(StaticContext statEnv) throws XQueryException {
if(!_analyzed) {
this._analyzed = true;
this._expr = _expr.staticAnalysis(statEnv);
final UnaryMinus op = new UnaryMinus();
op.staticAnalysis(statEnv, _expr);
this._op = op;
this._type = op.getReturnType();
}
return this;
}