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AspClassic.Parser/Token.cs

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+#define DEBUG
+using System;
+using System.Diagnostics;
+
+namespace AspClassic.Parser;
+
+/// <summary>
+/// The base class for all tokens. Contains line and column information as well as token type.
+/// </summary>
+public abstract class Token
+{
+	private readonly TokenType _Type;
+
+	private readonly Span _Span;
+
+	/// <summary>
+	/// The type of the token.
+	/// </summary>
+	public TokenType Type => _Type;
+
+	/// <summary>
+	/// The span of the token in the source text.
+	/// </summary>
+	public Span Span => _Span;
+
+	protected Token(TokenType type, Span span)
+	{
+		Debug.Assert(Enum.IsDefined(typeof(TokenType), type));
+		_Type = type;
+		_Span = span;
+	}
+
+	/// <summary>
+	/// Returns the unreserved keyword type of an identifier.
+	/// </summary>
+	/// <returns>The unreserved keyword type of an identifier, the token's type otherwise.</returns>
+	public virtual TokenType AsUnreservedKeyword()
+	{
+		return Type;
+	}
+}