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我想解析表达式

  • 一个
  • ++一个
  • 一个++
  • ++一个++
  • ++一个++++

前自增运算符优先于后自增运算符。

我拥有的解析器是:

public static readonly TokenListParser<LangToken, UnaryOperator> Increment = Token.EqualTo(LangToken.DoublePlus).Select(x => UnaryOperators.Increment);
public static readonly TokenListParser<LangToken, UnaryOperator> Decrement = Token.EqualTo(LangToken.DoubleMinus).Select(x => UnaryOperators.Decrement);

public static readonly TokenListParser<LangToken, Expression> Identifier = Token.EqualTo(LangToken.Identifier).Select(x => (Expression)new Id(x.ToStringValue()));

public static readonly TokenListParser<LangToken, Expression> A =
    from c in Parse.Ref(() => Expression)
    from op in Increment.Or(Decrement)
    select (Expression)new OpNode(op, c);

public static readonly TokenListParser<LangToken, Expression> B =
    from op in Increment.Or(Decrement)
    from c in Parse.Ref(() => Expression)
    select (Expression)new OpNode(op, c);

public static readonly TokenListParser<LangToken, Expression> Expression = A.Or(B).Or(Identifier);

但是,当我使用解析器解析像“a++”这样的简单表达式时Expression,测试会挂起。我想这是由于递归问题。

但是问题是什么以及如何解决呢?

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