Lwc: Private field declarations in classes (# support) error

[yaminm]

Description

I want to leverage the private field declarations in lwc classes

Steps to Reproduce

create a service class and use #

class  SapCarConfiguratorUtil {

    #MULTIPICKLIST = 'multipicklist';
    constructor(jsonResponse) {
        console.log(this.#MULTIPICKLIST);
   }

}

export {SapCarConfiguratorUtil}

https://developer.salesforce.com/docs/component-library/tools/playground

const your => (code) => here;

Expected Results

Deploy to org

Actual Results

ERROR deploying LightningComponentBundle lwc/sapCarConfiguratorUtil/sapCarConfiguratorUtil.js: LWC1509: Unexpected character '#' (7:4)

Version

API:46.0

[caridy]

@yaminm private fields are stage 3, once they reach stage 4, and are implemented in modern browsers, we will enable it with the corresponding transpilation down to IE11, for now... we keep waiting.

Btw, keep in mind that we provides protected fields at the moment, only those with @api are truly public, while regular fields are basically protected.