`Unexpected token 'export'` when exporting `wrapValidatorAsTypeguard` with a ts-node build

Hello, thanks for writing this fantastic library, it has been useful so far!

I’m getting the following error when building with ts-node:

$ cross-env NODE_ENV=development nodemon --exec ts-node -r dotenv-flow/config -r tsconfig-paths/register src/index.ts | pino-pretty -c
[nodemon] 2.0.19
[nodemon] to restart at any time, enter `rs`
[nodemon] watching path(s): *.*
[nodemon] watching extensions: ts,json
[nodemon] starting `ts-node -r dotenv-flow/config -r tsconfig-paths/register src/index.ts`
/home/lcsmuller/PF/quickstart-nodejs-rest/node_modules/json-schema-to-ts/lib/index.js:1
export { wrapCompilerAsTypeGuard, wrapValidatorAsTypeGuard, } from "json-schema-to-ts/lib/type-guards";
^^^^^^

SyntaxError: Unexpected token 'export'
    at Object.compileFunction (node:vm:352:18)
    at wrapSafe (node:internal/modules/cjs/loader:1033:15)
    at Module._compile (node:internal/modules/cjs/loader:1069:27)
    at Module._extensions..js (node:internal/modules/cjs/loader:1159:10)
    at Object.require.extensions.<computed> [as .js] (/home/lcsmuller/PF/quickstart-nodejs-rest/node_modules/ts-node/src/index.ts:1361:43)
    at Module.load (node:internal/modules/cjs/loader:981:32)
    at Function.Module._load (node:internal/modules/cjs/loader:822:12)
    at Module.require (node:internal/modules/cjs/loader:1005:19)
    at require (node:internal/modules/cjs/helpers:102:18)
    at Object.<anonymous> (/home/lcsmuller/PF/quickstart-nodejs-rest/src/common/schemas/utils/helpers.ts:3:1)
[nodemon] app crashed - waiting for file changes before starting...

This error only seems to trigger when I attempt to export a method that comes from a .js file (wrapValidatorAsTypeguard or wrapCompilerAsTypeguard)… It appears that ts-node cannot support export and import syntax by default, I think an easy fix for this would be targeting es5 instead (unless there is a rationale for not doing so). If you are busy, I can give it a try to write the PR.

[ThomasAribart]

Nice 👍 ! 2.6.2 is out so you can switch to an official version ! Cheers !

[ThomasAribart]

@lcsmuller Normally you shouldn’t need to worry about that, it’s done under the hood by node (I think ts-node will use commonjs imports though).

See https://webreflection.medium.com/cjs-vs-esm-5f8b90a4511a

TL:DR, cjs is the “old” way of importing JS, still needed for backward compatibility, esm is the “new” way. The package.json exposes two keys, main and module, so both code can be used.

Okay I’ll investigate some more 👍