initial commit

parser.cpp

@@ -0,0 +1,87 @@
+#include "parser.h"
+#include "exception.h"
+
+
+
+Parser::Parser() {
+	lexer = Lexer{};
+}
+
+std::unique_ptr<Node> Parser::parse(const std::string &code) {
+	lexer.parse(code);
+	lexer.debugTokens();	
+
+	if (lexer.tokenType() == TokenType::keyword_create && lexer.nextTokenType() == TokenType::keyword_table) {
+		return parse_create_table();
+	} if (lexer.tokenType() == TokenType::keyword_select) {
+		return parse_select();
+	}
+
+	return std::make_unique<Node>(NodeType::error);
+}
+
+std::unique_ptr<Node> Parser::parse_create_table() {
+	std::vector<ColDefNode> cols_def {};
+
+	lexer.skipToken(TokenType::keyword_create);
+	lexer.skipToken(TokenType::keyword_table);
+
+	if (lexer.tokenType() != TokenType::identifier)	{ /* TODO handle error */ }
+	std::string table_name = lexer.currentToken().token_string;
+	lexer.nextToken();
+	
+	lexer.skipToken(TokenType::open_paren);
+	do {
+		std::string	column_name;
+		ColumnType	column_type;
+		int		column_len {1};
+		bool		column_nullable {true};
+
+		// column name
+		if (lexer.tokenType() != TokenType::identifier)	{ /* TODO handle error */ }
+		column_name = lexer.currentToken().token_string;
+		lexer.nextToken();
+
+		// column type and optionaly len
+		if (lexer.tokenType() == TokenType::keyword_int) {
+			column_type = ColumnType::integer_type;
+			lexer.nextToken();
+		} else if (lexer.tokenType() == TokenType::keyword_float) {
+			column_type = ColumnType::float_type;
+			lexer.nextToken();
+		} else if (lexer.tokenType() == TokenType::keyword_varchar) {
+			column_type = ColumnType::varchar_type;
+			lexer.nextToken();
+			lexer.skipToken(TokenType::open_paren);
+			if (lexer.tokenType() == TokenType::int_number) {
+				column_len = std::stoi(lexer.currentToken().token_string);
+				lexer.nextToken();
+			} else { /* TODO handle error */ }
+			lexer.skipToken(TokenType::close_paren);
+		} else { /* TODO handle error */ }
+
+		if (lexer.tokenType() == TokenType::keyword_not) {
+			lexer.nextToken();
+			lexer.skipToken(TokenType::keyword_null);
+			column_nullable = false;
+		} else if (lexer.tokenType() == TokenType::keyword_null) {
+			lexer.nextToken();
+		}
+
+		cols_def.push_back(ColDefNode(column_name, column_type, column_len, column_nullable));
+
+		if (lexer.tokenType() == TokenType::comma) lexer.nextToken();
+		
+		// TODO in future constraints
+
+	} while (lexer.tokenType() != TokenType::close_paren);
+
+
+	return std::make_unique<CreateTableNode>(table_name, cols_def);
+}
+
+std::unique_ptr<Node> Parser::parse_select() {
+	std::vector<Node> exec_code {};
+
+	return std::make_unique<Node>(NodeType::not_implemented_yet);
+}