ts-evaluator

import { evaluate, createEvaluationContext } from 'ts-evaluator'; import ts, { createSourceFile, ScriptTarget, SyntaxKind } from 'typescript'; const code = ` const a = 10; const b = 'hello'; function greet(name: string) { return 'Hello, ' + name + '!'; } const result = greet(b); const obj = { x: a, y: result }; obj.x + 5; `; // Create a SourceFile from the code const sourceFile = createSourceFile('example.ts', code, ScriptTarget.ES2016, true); // Find the node to evaluate, e.g., 'obj.x + 5' const nodeToEvaluate = sourceFile.forEachChild(node => { if (ts.isBinaryExpression(node) && ts.isPropertyAccessExpression(node.left) && node.left.name.text === 'x') { return node; } return undefined; }); if (!nodeToEvaluate) { console.error('Could not find the node to evaluate.'); } else { // Create an evaluation context, optionally passing a TypeScript TypeChecker and policy options const context = createEvaluationContext({ typeChecker: ts.createProgram([sourceFile.fileName], { target: ScriptTarget.ES2016 }).getTypeChecker(), // Example policy: disallow I/O operations policy: { disableIO: true, disableNetwork: true }, // Initial lexical environment variables (if any) lexicalEnvironment: new Map() }); // Evaluate the node const evaluationResult = evaluate(nodeToEvaluate, context); if (evaluationResult.success) { console.log(`Evaluation successful! Value: ${evaluationResult.value}`); // Expected output: Evaluation successful! Value: 15 } else { console.error(`Evaluation failed: ${evaluationResult.reason}`); } }