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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 { FromClause } from "../models/Clause"; import { SqlTokenizer } from "./SqlTokenizer"; import { JoinClauseParser } from "./JoinClauseParser"; import { SourceExpressionParser } from "./SourceExpressionParser"; export class FromClauseParser { // 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 FROM clause is complete but there are additional tokens.`); } return result.value; } // Parse from lexeme array (was: parse) static parseFromLexeme(lexemes, index) { let idx = index; if (lexemes[idx].value !== 'from') { throw new Error(`Syntax error at position ${idx}: Expected 'FROM' keyword but found "${lexemes[idx].value}". FROM clauses must start with the FROM keyword.`); } idx++; if (idx >= lexemes.length) { throw new Error(`Syntax error: Unexpected end of input after 'FROM' keyword. The FROM clause requires a table reference.`); } // Parse the main source expression const sourceExpression = SourceExpressionParser.parseFromLexeme(lexemes, idx); idx = sourceExpression.newIndex; const join = JoinClauseParser.tryParse(lexemes, idx); idx = (join === null || join === void 0 ? void 0 : join.newIndex) || idx; if (join !== null) { const clause = new FromClause(sourceExpression.value, join.value); return { value: clause, newIndex: idx }; } else { const clause = new FromClause(sourceExpression.value, null); return { value: clause, newIndex: idx }; } } } //# sourceMappingURL=FromClauseParser.js.map