$ npx ts-node main.ts 
/home/alex/ton-build/node_modules/.pnpm/[email protected]/node_modules/typescript/lib/typescript.js:139
    for (let i = startIndex ?? 0; i < array.length; i++) {
                             ^

SyntaxError: Unexpected token ?
    at Module._compile (internal/modules/cjs/loader.js:723:23)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
    at Module.load (internal/modules/cjs/loader.js:653:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
    at Function.Module._load (internal/modules/cjs/loader.js:585:3)
    at Module.require (internal/modules/cjs/loader.js:692:17)
    at require (internal/modules/cjs/helpers.js:25:18)
    at attemptRequireWithV8CompileCache (/home/alex/ton-build/node_modules/.pnpm/[email protected]_@[email protected][email protected]/node_modules/ts-node/dist/util.js:104:16)
    at loadCompiler (/home/alex/ton-build/node_modules/.pnpm/[email protected]_@[email protected][email protected]/node_modules/ts-node/dist/configuration.js:237:56)
    at resolveAndLoadCompiler (/home/alex/ton-build/node_modules/.pnpm/[email protected]_@[email protected][email protected]/node_modules/ts-node/dist/configuration.js:226:16)