mirror of
https://gitee.com/langsisi_admin/serein-flow
synced 2026-03-03 00:00:49 +08:00
814 lines
31 KiB
C#
814 lines
31 KiB
C#
using Newtonsoft.Json.Linq;
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using Serein.Library;
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using Serein.Library.Utils;
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using Serein.Script.Node;
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using System.Collections.Generic;
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using System.Linq.Expressions;
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using System.Reflection;
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using System.Text;
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namespace Serein.Script
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{
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/// <summary>
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/// SereinScriptParser 用于解析 Serein 脚本语言的语法。
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/// </summary>
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public ref struct SereinScriptParser
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{
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private SereinScriptLexer _lexer;
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private Token _currentToken;
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public SereinScriptParser(string script)
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{
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_lexer = new SereinScriptLexer(script); // 语法分析
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_currentToken = _lexer.NextToken();
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}
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/// <summary>
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/// 解析脚本并返回 AST（抽象语法树）根节点。
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/// </summary>
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/// <returns></returns>
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public ASTNode Parse()
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{
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return Program();
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}
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private List<ASTNode> Statements { get; } = new List<ASTNode>();
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/// <summary>
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/// 解析整个程序，直到遇到文件结尾（EOF）为止。
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/// </summary>
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/// <returns></returns>
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private ASTNode Program()
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{
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Statements.Clear();
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while (_currentToken.Type != TokenType.EOF)
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{
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var astNode = Statement(); // 解析单个语句
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if (astNode == null)
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{
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continue;
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}
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Statements.Add(astNode); // 将解析得到的 AST 节点添加到语句列表中
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}
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var programNode = new ProgramNode(Statements);
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programNode.SetTokenInfo(_currentToken); // 程序节点，包含所有解析的语句列表
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SereinScriptTypeAnalysis typeAnalysis = new SereinScriptTypeAnalysis(programNode);
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return programNode;
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/*if (astNode is ClassTypeDefinitionNode)
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{
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statements = [astNode, ..statements]; // 类型定义置顶
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}
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else
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{
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statements.Add(astNode);
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}*/
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}
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/// <summary>
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/// 解析单个语句。
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/// </summary>
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/// <returns></returns>
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/// <exception cref="Exception"></exception>
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private ASTNode Statement()
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{
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// 处理其他语句（如表达式语句等）
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while (_currentToken.Type == TokenType.Semicolon)
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{
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_currentToken = _lexer.NextToken();
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}
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if(_currentToken.Type == TokenType.EOF)
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{
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return null;
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}
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if (_currentToken.Type == TokenType.Keyword && _currentToken.Value == "let")
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{
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// 处理 let 变量赋值语句
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return ParseLetAssignment();
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}
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if (_currentToken.Type == TokenType.Keyword && _currentToken.Value == "class")
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{
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// 加载类定义
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return ParseClassDefinition(); // 加载类，如果已经加载过，则忽略
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}
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if (_currentToken.Type == TokenType.Keyword && _currentToken.Value == "new")
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{
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var _peekToken = _lexer.PeekToken();
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if (_peekToken.Type == TokenType.Keyword && _peekToken.Value == "class")
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{
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// 重新加载类定义
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return ParseClassDefinition(); // 重新加载类
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}
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}
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if (_currentToken.Type == TokenType.Keyword && _currentToken.Value == "if")
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{
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// 处理 if 语句
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return ParseIf();
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}
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if (_currentToken.Type == TokenType.Keyword && _currentToken.Value == "while")
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{
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// 处理 while 循环语句
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return ParseWhile();
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}
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if (_currentToken.Type == TokenType.Keyword && _currentToken.Value == "return")
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{
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// 处理 return 语句
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return ParseReturn();
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}
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if (_currentToken.Type == TokenType.Identifier)
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{
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// 处理标识符，可能是函数调用、变量赋值或对象成员访问等行为
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return ParseIdentifier();
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}
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if (_currentToken.Type == TokenType.Null)
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{
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// 处理 null 语句
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return Expression();
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}
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/*if (_currentToken.Type == TokenType.Semicolon)
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{
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_currentToken = _lexer.NextToken();
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return null; // 表示空语句
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}*/
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throw new Exception("Unexpected statement: " + _currentToken.Value.ToString());
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}
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/// <summary>
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/// 从标识符解析方法调用、变量赋值、获取对象成员行为。
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/// （非符号、关键字）
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/// </summary>
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/// <returns></returns>
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private ASTNode ParseIdentifier()
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{
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// 检查标识符后是否跟有左圆括号
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var _tempToken = _lexer.PeekToken();
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if (_tempToken.Type == TokenType.ParenthesisLeft)
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{
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// 解析函数调用
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return ParseFunctionCall();
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}
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else if (_tempToken.Type == TokenType.Dot)
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{
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// 对象成员的获取
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return ParseMemberAccessOrAssignment();
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}
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else if (_tempToken.Type == TokenType.SquareBracketsLeft)
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{
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// 数组 index; 字典 key obj.Member[xxx];
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return ParseCollectionIndex();
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}
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else
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{
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// 不是函数调用，是变量赋值或其他
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return ParseAssignment();
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}
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}
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/// <summary>
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/// 解析赋值行为
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/// </summary>
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/// <returns></returns>
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/// <exception cref="Exception"></exception>
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private ASTNode ParseAssignment()
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{
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string variableName = _currentToken.Value.ToString();
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var _peekToken = _lexer.PeekToken();
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if (_peekToken.Type == TokenType.ParenthesisRight)
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{
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_currentToken = _lexer.NextToken(); // 消耗标识符
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return new IdentifierNode(variableName).SetTokenInfo(_currentToken);
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}
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if(_peekToken.Type == TokenType.Operator && _peekToken.Value == "=")
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{
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// 赋值行为
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_currentToken = _lexer.NextToken(); // 消耗标识符
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_currentToken = _lexer.NextToken(); // 消耗 "="
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var _tempToken = _lexer.PeekToken();
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ASTNode valueNode;
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if(_tempToken.Type == TokenType.Operator && _tempToken.Value != "=")
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{
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//_currentToken = _lexer.NextToken(); // 消耗操作符
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//_currentToken = _lexer.NextToken(); // 消耗操作符
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valueNode = Expression();
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}
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else if (_tempToken.Type == TokenType.ParenthesisLeft)
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{
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// 解析赋值右边的表达式
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// 是函数调用，解析函数调用
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valueNode = ParseFunctionCall();
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}
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else
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{
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// 解析赋值右边的字面量表达式
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valueNode = Expression();
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}
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return new AssignmentNode(variableName, valueNode).SetTokenInfo(_currentToken);
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}
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if (_peekToken.Type == TokenType.Dot)
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{
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// 可能是方法调用
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return ParseMemberAccessOrAssignment();
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}
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if(_peekToken.Type == TokenType.Operator)
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{
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return new IdentifierNode(variableName).SetTokenInfo(_currentToken);
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}
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throw new Exception($"Expected '{_currentToken.Value}' after variable name");
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}
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/// <summary>
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/// 解析 let 变量赋值行为
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/// </summary>
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/// <returns></returns>
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/// <exception cref="Exception"></exception>
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private ASTNode ParseLetAssignment()
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{
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_currentToken = _lexer.NextToken(); // Consume "let"
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string variable = _currentToken.Value.ToString(); // 变量名称
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_currentToken = _lexer.NextToken(); // Consume identifier
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ASTNode value;
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AssignmentNode assignmentNode;
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if (_currentToken.Type == TokenType.Semicolon)
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{
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// 定义一个变量，初始值为 null
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value = new NullNode();
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assignmentNode = new AssignmentNode(variable, value); // 生成node
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assignmentNode.SetTokenInfo(_currentToken); // 设置token信息
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}
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else
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{
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// 如果定义了变量，后面紧跟着操作符，且操作符不是“=”话视为异常
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// let value = obj;
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if (_currentToken.Type != TokenType.Operator || _currentToken.Value != "=")
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throw new Exception("Expected '=' after variable name");
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_currentToken = _lexer.NextToken(); // 消耗操作符（“=”）
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var nodeToken = _currentToken;
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value = Expression(); // 解析获取赋值表达式
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assignmentNode = new AssignmentNode(variable, value); // 生成node
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assignmentNode.SetTokenInfo(nodeToken); // 设置token信息
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_currentToken = _lexer.NextToken(); // 消耗分号
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}
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return assignmentNode;
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}
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/// <summary>
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/// 解析类定义
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/// </summary>
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/// <returns></returns>
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/// <exception cref="Exception"></exception>
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private ASTNode ParseClassDefinition()
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{
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var sb = new StringBuilder(); // 收集代码信息
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/*
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* 有两种定义类型的方式：
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* 1. class MyClass{}
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* 2. new class MyClass{}
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* 解析执行时，第二种方式定义的类，会顶掉其他地方创建的“MyClass”同名类型；
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*/
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var coreStartRangeIndex = _lexer.GetIndex() - "class".Length; // 从“class”开始锚定代码范围
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bool isOverlay = false; // 指示是否覆盖缓存中创建过的同名其它类型
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if (_currentToken.Value == "new")
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{
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isOverlay = true; // 重新加载类
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_currentToken = _lexer.NextToken(); // 消耗 new 关键字
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}
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_currentToken = _lexer.NextToken(); // 消耗 class 关键字
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var className = _currentToken.Value.ToString(); // 获取定义的类名
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_currentToken = _lexer.NextToken(); // 消耗类名
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if (_currentToken.Type != TokenType.BraceLeft || _currentToken.Value != "{")
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throw new Exception("Expected '{' after class definition");
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var classFields = new Dictionary<string, Type>();
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_currentToken = _lexer.NextToken(); // 消耗括号
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while (_currentToken.Type != TokenType.BraceRight)
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{
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// 获取类字段定义
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var fieldType = _currentToken.Value.ToString().ToTypeOfString(); // 获取字段的类型
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_currentToken = _lexer.NextToken(); // 消耗类型
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var fieldName = _currentToken.Value.ToString(); // 获取定义的类名
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_currentToken = _lexer.NextToken(); // 消耗字段名称
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classFields.Add(fieldName,fieldType); // 添加字段
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if (_currentToken.Type == TokenType.Semicolon
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&& _lexer.PeekToken().Type == TokenType.BraceRight)
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{
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// 如果遇到分号、大括号，退出字段定义。
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break;
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}
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else
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{
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_currentToken = _lexer.NextToken();
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}
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}
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_currentToken = _lexer.NextToken(); // 消耗类型定义 } 括号
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var typeDefinitionCode = _lexer.GetCoreContent(coreStartRangeIndex); // 收集类型定义的代码。（在Statement方法中开始收集的）
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var node = new ClassTypeDefinitionNode(classFields, className, isOverlay);
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_currentToken.Code = typeDefinitionCode;
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node.SetTokenInfo(_currentToken);
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// _currentToken = _lexer.NextToken();
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_currentToken = _lexer.NextToken();
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return node;
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}
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/// <summary>
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/// 解析对象实例化行为
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/// </summary>
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/// <returns></returns>
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/// <exception cref="Exception"></exception>
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public ASTNode ParseObjectInstantiation()
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{
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_currentToken = _lexer.NextToken(); // 消耗 new 关键字
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string typeName = _currentToken.Value.ToString(); // 获取类型名称
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_currentToken = _lexer.NextToken();
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if (_currentToken.Type != TokenType.ParenthesisLeft)
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throw new Exception("Expected '(' after function name");
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_currentToken = _lexer.NextToken(); // 消耗 "("
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var arguments = new List<ASTNode>();
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while (_currentToken.Type != TokenType.ParenthesisRight)
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{
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arguments.Add(Expression()); // 获取参数表达式
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if (_currentToken.Type == TokenType.Comma)
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{
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_currentToken = _lexer.NextToken(); // consume ","
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}
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}
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_currentToken = _lexer.NextToken(); // 消耗 ")"
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return new ObjectInstantiationNode(typeName, arguments).SetTokenInfo(_currentToken);
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}
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/// <summary>
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/// 解析集合索引行为（数组或字典）
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/// </summary>
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/// <returns></returns>
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/// <exception cref="Exception"></exception>
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public ASTNode ParseCollectionIndex()
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{
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var identifierNode = new IdentifierNode(_currentToken.Value.ToString()).SetTokenInfo(_currentToken);
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string collectionName = _currentToken.Value.ToString();
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//_lexer.NextToken(); // consume "["
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_currentToken = _lexer.NextToken(); // consume identifier
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// ParenthesisLeft
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if (_currentToken.Type != TokenType.SquareBracketsLeft)
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throw new Exception("Expected '[' after function name");
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_currentToken = _lexer.NextToken(); // consume "["
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ASTNode indexValue = Expression(); // get index value
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_currentToken = _lexer.NextToken(); // consume "]"
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return new CollectionIndexNode(identifierNode,indexValue).SetTokenInfo(_currentToken);
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}
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/// <summary>
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/// 获取对象成员
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/// </summary>
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/// <returns></returns>
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/// <exception cref="Exception"></exception>
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private ASTNode ParseMemberAccessOrAssignment()
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{
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var identifierNode = new IdentifierNode(_currentToken.Value).SetTokenInfo(_currentToken);
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_currentToken = _lexer.NextToken(); // 消耗当前标识符
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// 处理成员访问：identifier.member
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if (_currentToken.Type == TokenType.Dot)
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{
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_currentToken = _lexer.NextToken(); // 消耗 "."
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if (_currentToken.Type != TokenType.Identifier)
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{
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throw new Exception("Expected member name after dot.");
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}
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var memberName = _currentToken.Value;
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//_currentToken = _lexer.NextToken(); // 消耗成员名
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var _peekToken = _lexer.PeekToken();
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if (_peekToken.Type == TokenType.Operator && _peekToken.Value == "=")
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{
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// 成员赋值 obj.Member = xxx;
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_currentToken = _lexer.NextToken(); // 消耗 "="
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_currentToken = _lexer.NextToken(); // 消耗 "="
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var valueNode = Expression(); // 解析右值
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return new MemberAssignmentNode(identifierNode, memberName, valueNode).SetTokenInfo(_peekToken);
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}
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else
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{
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if(_peekToken.Type == TokenType.ParenthesisLeft)
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{
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// 成员方法调用 obj.Member(xxx);
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return ParseMemberFunctionCall(identifierNode);
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}
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else if (_peekToken.Type == TokenType.SquareBracketsLeft)
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{
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// 数组 index; 字典 key obj.Member[xxx];
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return ParseCollectionIndex();
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}
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else
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{
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_currentToken = _lexer.NextToken(); // 消耗 成员名称
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// 成员获取
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return new MemberAccessNode(identifierNode, memberName).SetTokenInfo(_currentToken);
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}
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}
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}
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return identifierNode;
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}
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/// <summary>
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/// 解析成员函数调用行为
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/// </summary>
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/// <param name="targetNode"></param>
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/// <returns></returns>
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/// <exception cref="Exception"></exception>
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private ASTNode ParseMemberFunctionCall(ASTNode targetNode)
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{
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string functionName = _currentToken.Value.ToString(); // 函数名称
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_currentToken = _lexer.NextToken(); // consume identifier
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if (_currentToken.Type != TokenType.ParenthesisLeft)
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throw new Exception("Expected '(' after function name");
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_currentToken = _lexer.NextToken(); // consume "("
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var arguments = new List<ASTNode>();
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while (_currentToken.Type != TokenType.ParenthesisRight)
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{
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// 获取参数表达式
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var arg = Expression();
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_currentToken = _lexer.NextToken(); // consume arg
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arguments.Add(arg); // 添加到参数列表
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if (_currentToken.Type == TokenType.Comma)
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{
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_currentToken = _lexer.NextToken(); // consume ","
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}
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if (_currentToken.Type == TokenType.Semicolon)
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{
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break; // consume ";"
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}
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}
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//_currentToken = _lexer.NextToken(); // consume ")"
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return new MemberFunctionCallNode(targetNode, functionName, arguments).SetTokenInfo(_currentToken);
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}
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/// <summary>
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/// 解析函数调用行为
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/// </summary>
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/// <returns></returns>
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/// <exception cref="Exception"></exception>
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private ASTNode ParseFunctionCall()
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{
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string functionName = _currentToken.Value.ToString();
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_currentToken = _lexer.NextToken(); // consume identifier
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if (_currentToken.Type != TokenType.ParenthesisLeft)
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throw new Exception("Expected '(' after function name");
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|
||
_currentToken = _lexer.NextToken(); // consume "("
|
||
|
||
var arguments = new List<ASTNode>();
|
||
bool isBreak = false;
|
||
while (_currentToken.Type != TokenType.ParenthesisRight)
|
||
{
|
||
var arg = Expression(); // 获取参数表达式
|
||
_currentToken = _lexer.NextToken(); // consume arg
|
||
arguments.Add(arg);
|
||
if (_currentToken.Type == TokenType.Comma)
|
||
{
|
||
_currentToken = _lexer.NextToken(); // consume ","
|
||
}
|
||
if (_currentToken.Type == TokenType.Semicolon)
|
||
{
|
||
isBreak = true;
|
||
break; // consume ";"
|
||
}
|
||
}
|
||
if(!isBreak)
|
||
_currentToken = _lexer.NextToken(); // consume ")"
|
||
|
||
|
||
//var node = Statements[^1];
|
||
//if (node is MemberAccessNode memberAccessNode)
|
||
//{
|
||
// // 上一个是对象
|
||
// return new MemberFunctionCallNode(memberAccessNode, functionName, arguments).SetTokenInfo(_currentToken);
|
||
//}
|
||
//if (node is IdentifierNode identifierNode)
|
||
//{
|
||
// return new MemberFunctionCallNode(identifierNode, functionName, arguments).SetTokenInfo(_currentToken);
|
||
//}
|
||
|
||
// 从挂载的函数表寻找对应的函数，尝试调用
|
||
return new FunctionCallNode(functionName, arguments).SetTokenInfo(_currentToken);
|
||
|
||
|
||
}
|
||
|
||
/// <summary>
|
||
/// 解析 return 语句。
|
||
/// </summary>
|
||
/// <returns></returns>
|
||
public ASTNode ParseReturn()
|
||
{
|
||
_currentToken = _lexer.NextToken();
|
||
if(_currentToken.Type == TokenType.Semicolon)
|
||
{
|
||
return new ReturnNode().SetTokenInfo(_currentToken); // 返回空的 ReturnNode
|
||
}
|
||
var resultValue = Expression(); // 获取返回值表达式
|
||
_currentToken = _lexer.NextToken();
|
||
return new ReturnNode(resultValue).SetTokenInfo(_currentToken);
|
||
}
|
||
|
||
|
||
/// <summary>
|
||
/// 解析 if 语句。
|
||
/// </summary>
|
||
/// <returns></returns>
|
||
/// <exception cref="Exception"></exception>
|
||
private ASTNode ParseIf()
|
||
{
|
||
_currentToken = _lexer.NextToken(); // Consume "if"
|
||
_currentToken = _lexer.NextToken(); // Consume "("
|
||
ASTNode condition = Expression();
|
||
_currentToken = _lexer.NextToken(); // Consume ")"
|
||
|
||
// 确保遇到左大括号 { 后进入代码块解析
|
||
if (_currentToken.Type != TokenType.BraceLeft)
|
||
{
|
||
throw new Exception("Expected '{' after if condition");
|
||
}
|
||
_currentToken = _lexer.NextToken(); // Consume "{"
|
||
|
||
// 解析大括号中的语句
|
||
List<ASTNode> trueBranch = new List<ASTNode>();
|
||
List<ASTNode> falseBranch = new List<ASTNode>();
|
||
while (_currentToken.Type != TokenType.BraceRight && _currentToken.Type != TokenType.EOF)
|
||
{
|
||
var astNode = Statement(); // 解析 if 分支中的语句
|
||
if (astNode != null)
|
||
{
|
||
trueBranch.Add(astNode); // 将 if 分支的语句添加到 trueBranch 中
|
||
}
|
||
}
|
||
// 确保匹配右大括号 }
|
||
if (_currentToken.Type != TokenType.BraceRight)
|
||
{
|
||
throw new Exception("Expected '}' after if block");
|
||
}
|
||
_currentToken = _lexer.NextToken(); // Consume "}"
|
||
if (_currentToken.Type == TokenType.Keyword && _currentToken.Value == "else")
|
||
{
|
||
_currentToken = _lexer.NextToken(); // Consume "{"
|
||
_currentToken = _lexer.NextToken(); // Consume "{"
|
||
while (_currentToken.Type != TokenType.BraceRight && _currentToken.Type != TokenType.EOF)
|
||
{
|
||
var astNode = Statement(); // 解析 else 分支中的语句
|
||
if (astNode != null)
|
||
{
|
||
falseBranch.Add(astNode); // 将 else 分支的语句添加到 falseBranch 中
|
||
}
|
||
}
|
||
// 确保匹配右大括号 }
|
||
if (_currentToken.Type != TokenType.BraceRight)
|
||
{
|
||
throw new Exception("Expected '}' after if block");
|
||
}
|
||
_currentToken = _lexer.NextToken(); // Consume "}"
|
||
}
|
||
|
||
|
||
return new IfNode(condition, trueBranch, falseBranch).SetTokenInfo(_currentToken);
|
||
}
|
||
|
||
/// <summary>
|
||
/// 解析 while 循环语句。
|
||
/// </summary>
|
||
/// <returns></returns>
|
||
private ASTNode ParseWhile()
|
||
{
|
||
_currentToken = _lexer.NextToken(); // Consume "while"
|
||
_currentToken = _lexer.NextToken(); // Consume "("
|
||
ASTNode condition = Expression();
|
||
_currentToken = _lexer.NextToken(); // Consume ")"
|
||
_currentToken = _lexer.NextToken(); // Consume "{"
|
||
List<ASTNode> body = new List<ASTNode>();
|
||
while (_currentToken.Type != TokenType.BraceRight)
|
||
{
|
||
body.Add(Statement()); // 解析循环体中的语句
|
||
}
|
||
_currentToken = _lexer.NextToken(); // Consume "}"
|
||
return new WhileNode(condition, body).SetTokenInfo(_currentToken);
|
||
}
|
||
|
||
/// <summary>
|
||
/// 解析表达式。
|
||
/// </summary>
|
||
/// <returns></returns>
|
||
private ASTNode Expression()
|
||
{
|
||
ASTNode left = Term();
|
||
while (_currentToken.Type == TokenType.Operator && (
|
||
_currentToken.Value == "+" || _currentToken.Value == "-" ||
|
||
_currentToken.Value == "*" || _currentToken.Value == "/"))
|
||
{
|
||
string op = _currentToken.Value.ToString();
|
||
_currentToken = _lexer.NextToken();
|
||
ASTNode right = Term();
|
||
left = new BinaryOperationNode(left, op, right).SetTokenInfo(_currentToken);
|
||
}
|
||
return left;
|
||
}
|
||
|
||
|
||
/// <summary>
|
||
/// 解析项（Term），用于处理加减乘除等运算符。
|
||
/// </summary>
|
||
/// <returns></returns>
|
||
private ASTNode Term()
|
||
{
|
||
ASTNode left = Factor();
|
||
while (_currentToken.Type == TokenType.Operator &&
|
||
(_currentToken.Value == "<" || _currentToken.Value == ">" ||
|
||
_currentToken.Value == "<=" || _currentToken.Value == ">=" ||
|
||
_currentToken.Value == "==" || _currentToken.Value == "!="))
|
||
{
|
||
string op = _currentToken.Value.ToString();
|
||
_currentToken = _lexer.NextToken();
|
||
ASTNode right = Factor();
|
||
left = new BinaryOperationNode(left, op, right).SetTokenInfo(_currentToken);
|
||
}
|
||
return left;
|
||
}
|
||
|
||
/// <summary>
|
||
/// 解析因子（Factor），用于处理基本的字面量、标识符、括号表达式等。
|
||
/// </summary>
|
||
/// <returns></returns>
|
||
/// <exception cref="Exception"></exception>
|
||
private ASTNode Factor()
|
||
{
|
||
#region 返回字面量
|
||
if (_currentToken.Type == TokenType.Null)
|
||
{
|
||
_currentToken = _lexer.NextToken(); // 消耗 null
|
||
return new NullNode().SetTokenInfo(_currentToken);
|
||
}
|
||
if (_currentToken.Type == TokenType.Boolean)
|
||
{
|
||
var value = bool.Parse(_currentToken.Value);
|
||
_currentToken = _lexer.NextToken(); // 消耗布尔量
|
||
return new BooleanNode(value).SetTokenInfo(_currentToken);
|
||
}
|
||
if (_currentToken.Type == TokenType.String)
|
||
{
|
||
var text = _currentToken.Value;
|
||
var node = new StringNode(text).SetTokenInfo(_currentToken);
|
||
_currentToken = _lexer.NextToken(); // 消耗字符串
|
||
return node;
|
||
}
|
||
if (_currentToken.Type == TokenType.Char)
|
||
{
|
||
var text = _currentToken.Value;
|
||
_currentToken = _lexer.NextToken(); // 消耗Char
|
||
return new CharNode(text).SetTokenInfo(_currentToken);
|
||
}
|
||
if( _currentToken.Type == TokenType.InterpolatedString)
|
||
{
|
||
// 暂未实现插值字符串
|
||
// 可能是插值字符串；
|
||
// let context = $"a{A}b{B}c";
|
||
// let context = "a" + A + "b" + B + c;
|
||
_currentToken = _lexer.NextToken(); // 消耗字符串
|
||
while (_currentToken.Type == TokenType.String) {
|
||
}
|
||
}
|
||
|
||
if (_currentToken.Type == TokenType.NumberInt)
|
||
{
|
||
var value = int.Parse(_currentToken.Value);
|
||
_currentToken = _lexer.NextToken(); // 消耗 int 整型
|
||
return new NumberIntNode(value).SetTokenInfo(_currentToken);
|
||
}
|
||
|
||
if (_currentToken.Type == TokenType.NumberLong)
|
||
{
|
||
var value = long.Parse(_currentToken.Value);
|
||
_currentToken = _lexer.NextToken(); // 消耗
|
||
return new NumberLongNode(value).SetTokenInfo(_currentToken);
|
||
}
|
||
|
||
if (_currentToken.Type == TokenType.NumberFloat)
|
||
{
|
||
var value = float.Parse(_currentToken.Value);
|
||
_currentToken = _lexer.NextToken(); // 消耗数字
|
||
return new NumberFloatNode(value).SetTokenInfo(_currentToken);
|
||
}
|
||
|
||
if (_currentToken.Type == TokenType.NumberDouble)
|
||
{
|
||
var value = float.Parse(_currentToken.Value);
|
||
_currentToken = _lexer.NextToken(); // 消耗数字
|
||
return new NumberDoubleNode(value).SetTokenInfo(_currentToken);
|
||
}
|
||
#endregion
|
||
|
||
// 方法调用
|
||
if (_currentToken.Type == TokenType.ParenthesisLeft)
|
||
{
|
||
_currentToken = _lexer.NextToken(); // 消耗 "("
|
||
var expr = Expression();
|
||
if (_currentToken.Type != TokenType.ParenthesisRight)
|
||
throw new Exception("非预期的符号，预期符号为\")\"。");
|
||
_currentToken = _lexer.NextToken(); // 消耗 ")"
|
||
return expr;
|
||
}
|
||
|
||
// 创建对象
|
||
if (_currentToken.Type == TokenType.Keyword && _currentToken.Value == "new")
|
||
{
|
||
// 可能是对象实例化
|
||
return ParseObjectInstantiation();
|
||
}
|
||
|
||
// 标识符节点
|
||
if (_currentToken.Type == TokenType.Identifier)
|
||
{
|
||
var identifier = _currentToken.Value; // 标识符字面量
|
||
var _identifierPeekToken = _lexer.PeekToken();
|
||
// 该标识符是方法调用
|
||
if (_identifierPeekToken.Type == TokenType.ParenthesisLeft)
|
||
{
|
||
// 可能是函数调用
|
||
return ParseFunctionCall();
|
||
}
|
||
|
||
// 需要从该标识符调用另一个标识符
|
||
if (_identifierPeekToken.Type == TokenType.Dot)
|
||
{
|
||
// 可能是成员访问或成员赋值
|
||
return ParseMemberAccessOrAssignment(); // 二元操作中获取对象成员
|
||
}
|
||
|
||
|
||
// 数组 index; 字典 key obj.Member[xxx];
|
||
if (_identifierPeekToken.Type == TokenType.SquareBracketsLeft)
|
||
{
|
||
return ParseCollectionIndex();
|
||
}
|
||
|
||
_currentToken = _lexer.NextToken(); // 消耗标识符
|
||
return new IdentifierNode(identifier.ToString()).SetTokenInfo(_currentToken);
|
||
}
|
||
|
||
|
||
throw new Exception("Unexpected factor: " + _currentToken.Value.ToString());
|
||
}
|
||
}
|
||
|
||
}
|
