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rawsql-ts

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[beta]High-performance SQL parser and AST analyzer written in TypeScript. Provides fast parsing and advanced transformation capabilities.

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import { WithClause } from "../models/Clause"; import { TokenType } from "../models/Lexeme"; import { SqlTokenizer } from "./SqlTokenizer"; import { CommonTableParser } from "./CommonTableParser"; export class WithClauseParser { // Parse SQL string to AST (was: parse) static parse(query) { const tokenizer = new SqlTokenizer(query); // Initialize tokenizer const lexemes = tokenizer.readLexmes(); // Get tokens // Parse const result = this.parseFromLexeme(lexemes, 0); // Error if there are remaining tokens if (result.newIndex < lexemes.length) { throw new Error(`Syntax error: Unexpected token "${lexemes[result.newIndex].value}" at position ${result.newIndex}. The WITH clause is complete but there are additional tokens.`); } return result.value; } // Parse from lexeme array (was: parse) static parseFromLexeme(lexemes, index) { let idx = index; // Expect WITH keyword if (idx < lexemes.length && lexemes[idx].value.toLowerCase() === "with") { idx++; } else { throw new Error(`Syntax error at position ${idx}: Expected WITH keyword.`); } // Check for RECURSIVE keyword const recursive = idx < lexemes.length && lexemes[idx].value.toLowerCase() === "recursive"; if (recursive) { idx++; } // Parse CTEs const tables = []; // Parse first CTE (required) const firstCte = CommonTableParser.parseFromLexeme(lexemes, idx); tables.push(firstCte.value); idx = firstCte.newIndex; // Parse additional CTEs (optional) while (idx < lexemes.length && (lexemes[idx].type & TokenType.Comma)) { idx++; // Skip comma const cteResult = CommonTableParser.parseFromLexeme(lexemes, idx); tables.push(cteResult.value); idx = cteResult.newIndex; } // Create WITH clause return { value: new WithClause(recursive, tables), newIndex: idx }; } } //# sourceMappingURL=WithClauseParser.js.map