110 lines
2.1 KiB
C++
110 lines
2.1 KiB
C++
#include "Parser.hpp"
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namespace wg
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{
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/*explicit*/ Parser::Parser()
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{
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}
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/*virtual*/ Parser::~Parser()
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{
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}
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std::shared_ptr<Node> Parser::parse(std::vector<std::shared_ptr<Node>>
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const& tokens)
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{
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m_cursor = 0;
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m_tokens = tokens;
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return parse_prog();
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}
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Loc Parser::loc() const
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{
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return m_tokens[m_cursor]->loc();
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}
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std::shared_ptr<Node> Parser::consume(NodeType type)
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{
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auto current = m_tokens[m_cursor];
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if (current->type() != type)
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{
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std::stringstream ss;
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ss << "type mismatch, expected '"
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<< (NodeTypeStr[type] + strlen("NODE_"))
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<< "', got '"
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<< (NodeTypeStr[current->type()] + strlen("NODE_"))
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<< "'";
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loc().error<syntax_error>(ss);
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}
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else
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{
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return consume();
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}
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return nullptr;
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}
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std::shared_ptr<Node> Parser::consume()
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{
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WG_ASSERT(m_cursor < m_tokens.size(), "cannot consume");
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auto node = m_tokens[m_cursor];
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m_cursor++;
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return node;
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}
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bool Parser::type_is(NodeType type, int lookahead)
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{
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if (m_cursor + lookahead >= m_tokens.size())
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{
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return false;
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}
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return m_tokens[m_cursor + lookahead]->type() == type;
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}
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bool Parser::type_isnt(NodeType type, int lookahead)
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{
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return !type_is(type, lookahead);
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}
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std::shared_ptr<Node> Parser::make_node(NodeType type) const
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{
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return std::make_shared<Node>(type, "", loc());
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}
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std::shared_ptr<Node> Parser::parse_prog()
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{
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auto node = std::make_shared<Node>(NODE_PROG, "", Loc {});
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while (m_cursor < m_tokens.size())
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{
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node->add_child(parse_instr());
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}
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return node;
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}
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std::shared_ptr<Node> Parser::parse_instr()
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{
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return parse_dir();
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}
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std::shared_ptr<Node> Parser::parse_dir()
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{
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auto node = make_node(NODE_DIR);
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consume(NODE_HASH);
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node->add_child(consume(NODE_IDENT));
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node->add_child(parse_expr());
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return node;
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}
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std::shared_ptr<Node> Parser::parse_expr()
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{
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return consume(NODE_IDENT);
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}
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}
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