Method optimize

basex-core/src/main/java/org/basex/query/expr/gflwor/For.java:121–145

(final CompileContext cc)

  }

  @Override
  public For optimize(final CompileContext cc) throws QueryException {
    // for $a as xs:integer in $array → for $a as xs:integer in data($array)
    final SeqType dt = var.declType;
    if(dt != null && dt.instanceOf(Types.ANY_ATOMIC_TYPE_ZM) && expr.seqType().mayBeWrapped()) {
      expr = cc.function(DATA, info, expr);
    }

    // remove empty flag if expression is never empty; assign type to clause and variable
    final SeqType st = expr.seqType();
    if(st.oneOrMore()) empty = false;
    exprType.assign(st.with(empty ? st.zero() ? Occ.ZERO : Occ.ZERO_OR_ONE : Occ.EXACTLY_ONE));

    var.refineType(seqType(), size(), cc);
    var.expr(expr);
    if(pos != null) {
      pos.refineType(Types.INTEGER_O, 1, cc);
      pos.expr(Itr.ZERO);
    }
    if(score != null) {
      score.refineType(Types.DOUBLE_O, 1, cc);
      score.expr(Dbl.ZERO);
    }
    return this;
  }

  @Override
  public For copy(final CompileContext cc, final IntObjectMap<Var> vm) {