67 lines
1.4 KiB
C#
67 lines
1.4 KiB
C#
namespace Canon.Core.GrammarParser;
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/// <summary>
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/// LR语法中的一个项目集规范族
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/// 也就是自动机中的一个状态
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/// </summary>
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public class LrState : IEquatable<LrState>
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{
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/// <summary>
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/// 项目集规范族
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/// </summary>
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public required HashSet<Expression> Expressions { get; init; }
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/// <summary>
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/// 自动机的迁移规则
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/// </summary>
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public Dictionary<TerminatorBase, LrState> Transformer { get; } = [];
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public bool Equals(LrState? other)
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{
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if (other is null)
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{
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return false;
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}
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if (Expressions.Count != other.Expressions.Count)
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{
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return false;
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}
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// 如果两个集合的大小相等，且一个是另一个的子集，那么两个集合相等。
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return Expressions.IsSubsetOf(other.Expressions);
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}
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public override bool Equals(object? obj)
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{
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if (obj is not LrState other)
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{
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return false;
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}
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return Equals(other);
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}
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public override int GetHashCode()
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{
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int hash = 0;
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foreach (Expression expression in Expressions)
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{
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hash ^= expression.GetHashCode();
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}
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return hash;
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}
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public static bool operator ==(LrState a, LrState b)
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{
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return a.Equals(b);
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}
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public static bool operator !=(LrState a, LrState b)
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{
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return !a.Equals(b);
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}
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}
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