51 lines
1.6 KiB
C#
51 lines
1.6 KiB
C#
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// Copyright (c) Ivan Bondarev, Stanislav Mikhalkovich (for details please see \doc\copyright.txt)
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// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
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using System;
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using System.Collections.Generic;
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using System.Linq;
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using System.Text;
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using PascalABCCompiler.SyntaxTree;
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namespace SyntaxVisitors.SugarVisitors
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{
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/// <summary>
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/// А здесь не только замена кортежа - здесь оптимизация (a,b) := (1,2) и var (a,b) := (1,2)
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/// </summary>
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public class LetExprVisitor : BaseChangeVisitor
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{
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public static LetExprVisitor New
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{
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get { return new LetExprVisitor(); }
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}
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private int num = 0;
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public string UniqueName()
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{
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num++;
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return "#let_expr_vis"+num.ToString();
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}
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public override void visit(let_var_expr let_ex)
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{
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// Сгенерировать var_def_statement
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var vds = new var_statement(let_ex.id, let_ex.ex, let_ex.source_context);
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Replace(let_ex, let_ex.id);
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// Подняться до statement
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syntax_tree_node p = let_ex;
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while (p != null && !(p is statement))
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p = p.Parent;
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if (p == null)
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new SyntaxVisitorError("LET_EXPR_CANNOT_BE_IN_THIS_CONTEXT", let_ex);
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var stat = p as statement;
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var sl = new List<statement>();
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sl.Add(vds);
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sl.Add(stat);
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ReplaceStatementUsingParent(stat, sl);
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ProcessNode(vds);
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ProcessNode(stat);
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}
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}
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}
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