class - Can static methods in javascript call non static -

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i curious "undefined not function" error. consider following class:

var flareerror = require('../flare_error.js');  class currency {    constructor() {     this._currencystore = [];   }    static store(currency) {     (var key in currency) {       if (currency.hasownproperty(key) && currency[key] !== "") {          if (object.keys(json.parse(currency[key])).length > 0) {           var currencyobject = json.parse(currency[key]);           this.currencyvalidator(currencyobject);            currencyobject["current_amount"] = 0;            this._currencystore.push(currencyobject);         }       }     }   }     currencyvalidator(currencyjson) {     if (!currencyjson.hasownproperty('name')) {       flareerror.error('currency must have name attribute in json.');     }      if (!currencyjson.hasownproperty('description')) {       flareerror.error('currency must have description attribute in json.');     }      if (!currencyjson.hasownproperty('icon')) {       flareerror.error('currency must have icon attribute in json.');     }   }    static getcurrencystore() {     return this._currencystore;   }  };  module.exports = currency;

refactoring aside, issue on line: this.currencyvalidator(currencyobject); error "undefined not function"

i assume because have static method who's internals call non static method? non static method have static? , if concept of this.methodname still work?

no, static method cannot call non-static method.

consider have objects a , b, both instances of currency. currencyvalidator exists on 2 objects. store() belongs class currency itself, not 1 of objects. so, in currency.store(), how know object call currencyvalidator() on? simple answer doesn't can't. 1 of pitfalls of using static methods , 1 of reasons people urge against them.

regardless, can around passing a currency.store(), , calling a.currencyvalidator() instead.


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