42 lines
926 B
C#
42 lines
926 B
C#
using System;
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using Ast;
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public class Visitor<T> {
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public Func<int, T> Int { get; set; }
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public Func<string, T> String { get; set; }
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}
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namespace Ast {
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public interface Expr {
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T Match_<T>(Visitor<T> c);
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}
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public abstract class Const<T> : Expr {
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public readonly T value;
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public Const(T value) { this.value = value; }
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public abstract U Match_<U>(Visitor<U> c);
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}
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public class Int : Const<int> {
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public Int(int x) : base(x) {}
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public override T Match_<T>(Visitor<T> c) => c.Int(value);
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}
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public class String : Const<string> {
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public String(string x) : base(x) {}
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public override T Match_<T>(Visitor<T> c) => c.String(value);
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}
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}
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public static class AstExtensionMethods {
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public static T Match<T>(
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this Ast.Expr e,
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Func<int, T> Int,
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Func<string, T> String
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) {
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return e.Match_(new Visitor<T> {
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Int = Int,
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String = String
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});
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}
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} |