EPPlus/FormulaParsing/ExpressionGraph/FunctionCompilers/LookupFunctionCompiler.cs

/*******************************************************************************
 * You may amend and distribute as you like, but don't remove this header!
 *
 * EPPlus provides server-side generation of Excel 2007/2010 spreadsheets.
 * See http://www.codeplex.com/EPPlus for details.
 *
 * Copyright (C) 2011  Jan Källman
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.

 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * The GNU Lesser General Public License can be viewed at http://www.opensource.org/licenses/lgpl-license.php
 * If you unfamiliar with this license or have questions about it, here is an http://www.gnu.org/licenses/gpl-faq.html
 *
 * All code and executables are provided "as is" with no warranty either express or implied.
 * The author accepts no liability for any damage or loss of business that this product may cause.
 *
 * Code change notes:
 *
 * Author							Change						Date
 * ******************************************************************************
 * Mats Alm   		                Added       		        2013-03-01 (Prior file history on https://github.com/swmal/ExcelFormulaParser)
 *******************************************************************************/

using System.Collections.Generic;
using OfficeOpenXml.FormulaParsing.Excel.Functions;

namespace OfficeOpenXml.FormulaParsing.ExpressionGraph.FunctionCompilers;

public class LookupFunctionCompiler : FunctionCompiler {
  public LookupFunctionCompiler(ExcelFunction function)
      : base(function) {}

  public override CompileResult Compile(IEnumerable<Expression> children, ParsingContext context) {
    var args = new List<FunctionArgument>();
    Function.BeforeInvoke(context);
    var firstChild = true;
    foreach (var child in children) {
      if (!firstChild || Function.SkipArgumentEvaluation) {
        child.ParentIsLookupFunction = Function.IsLookupFuction;
      } else {
        firstChild = false;
      }
      var arg = child.Compile();
      BuildFunctionArguments(arg != null ? arg.Result : null, args);
    }
    return Function.Execute(args, context);
  }
}