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AspClassic.Parser/Span.cs

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+namespace AspClassic.Parser;
+
+/// <summary>
+/// Stores the location of a span of text.
+/// </summary>
+/// <remarks>The end location is exclusive.</remarks>
+public struct Span
+{
+	private readonly Location _Start;
+
+	private readonly Location _Finish;
+
+	/// <summary>
+	/// The start location of the span.
+	/// </summary>
+	public Location Start => _Start;
+
+	/// <summary>
+	/// The end location of the span.
+	/// </summary>
+	public Location Finish => _Finish;
+
+	/// <summary>
+	/// Whether the locations in the span are valid.
+	/// </summary>
+	public bool IsValid => Start.IsValid && Finish.IsValid;
+
+	/// <summary>
+	/// Constructs a new span with a specific start and end location.
+	/// </summary>
+	/// <param name="start">The beginning of the span.</param>
+	/// <param name="finish">The end of the span.</param>
+	public Span(Location start, Location finish)
+	{
+		this = default(Span);
+		_Start = start;
+		_Finish = finish;
+	}
+
+	/// <summary>
+	/// Compares two specified Span values to see if they are equal.
+	/// </summary>
+	/// <param name="left">One span to compare.</param>
+	/// <param name="right">The other span to compare.</param>
+	/// <returns>True if the spans are the same, False otherwise.</returns>
+	public static bool operator ==(Span left, Span right)
+	{
+		return left.Start.Index == right.Start.Index && left.Finish.Index == right.Finish.Index;
+	}
+
+	/// <summary>
+	/// Compares two specified Span values to see if they are not equal.
+	/// </summary>
+	/// <param name="left">One span to compare.</param>
+	/// <param name="right">The other span to compare.</param>
+	/// <returns>True if the spans are not the same, False otherwise.</returns>
+	public static bool operator !=(Span left, Span right)
+	{
+		return left.Start.Index != right.Start.Index || left.Finish.Index != right.Finish.Index;
+	}
+
+	public override string ToString()
+	{
+		return Start.ToString() + " - " + Finish.ToString();
+	}
+
+	public override bool Equals(object obj)
+	{
+		if (obj is Span)
+		{
+			return this == (Span)obj;
+		}
+		return false;
+	}
+
+	public override int GetHashCode()
+	{
+		return checked((int)((Start.Index ^ Finish.Index) & 0xFFFFFFFFu));
+	}
+}