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46 lines
946 B
C++
46 lines
946 B
C++
#pragma once
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#include <list>
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#include <Poco/SharedPtr.h>
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#include <DB/Core/Types.h>
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#include <DB/Parsers/IParser.h>
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#include <iostream>
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namespace DB
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{
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/** Базовый класс для большинства парсеров
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*/
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class IParserBase : public IParser
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{
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public:
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bool parse(Pos & pos, Pos end, ASTPtr & node, Pos & max_parsed_pos, Expected & expected)
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{
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Pos new_max_parsed_pos = pos;
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Expected new_expected = getName();
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bool res = parseImpl(pos, end, node, new_max_parsed_pos, new_expected);
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if (new_max_parsed_pos > max_parsed_pos)
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max_parsed_pos = new_max_parsed_pos;
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if (new_max_parsed_pos >= max_parsed_pos)
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expected = new_expected;
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if (!res)
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node = nullptr;
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if (pos > end)
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throw Exception("Logical error: pos > end.", ErrorCodes::LOGICAL_ERROR);
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return res;
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}
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protected:
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virtual bool parseImpl(Pos & pos, Pos end, ASTPtr & node, Pos & max_parsed_pos, Expected & expected) = 0;
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};
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}
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