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** This file is part of the Qt VS Tools.
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using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace QtVsTools.SyntaxAnalysis
{
    /// <summary>
    /// Sequential composition
    /// </summary>
    public partial class RegExprSequence : RegExpr
    {
        public IEnumerable<RegExpr> Exprs { get; set; }

        protected override IEnumerable<RegExpr> OnRender(RegExpr defaultTokenWs, RegExpr parent,
            StringBuilder pattern, ref RenderMode mode, Stack<Token> tokenStack)
        {
            base.OnRender(defaultTokenWs, parent, pattern, ref mode, tokenStack);
            return Exprs;
        }
    }

    public abstract partial class RegExpr
    {
        public static RegExprSequence Concat(params RegExpr[] rxs)
        {
            return new RegExprSequence
            {
                Exprs = rxs.SelectMany(rx => rx is RegExprSequence
                    ? ((RegExprSequence)rx).Exprs
                    : Items(rx))
            };
        }

        public static RegExprSequence operator &(RegExpr rx1, RegExpr rx2)
        {
            return Concat(rx1, rx2);
        }
    }
}