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Javascript – Getter returns undefined in if statement. Seems not working for comparisons

I have a ClockObj which has an AlarmObj in a "HAS A" OOP relationship. Or should I say injected through the constructor.

Inside the AlarmObj I have a isAlarmOn boolean variable. I am returning it using getter.

class AlarmObj {
  isAlarmOn = true
  get getAlarmOnOffStatus() {
    return this.isAlarmOn;
  }
}

class ClockObj {

  constructor(AlarmObjArg) {

    this.AlarmObj = AlarmObjArg

    if (this.AlarmObj.getAlarmOnOffStatus === true) {
      console.log('works')
    }
  }
}

AlarmObj = new AlarmObj();

new ClockObj(AlarmObj)

However it return undefined and when debugging I found that getter is called after the if statement.
Is that normal behavior or something is wrong here ?

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2

Answers


  1. Chosen as BEST ANSWER
    0

    My bad. Yes, the getter was returning undefined but that was because the variable itself was undefined. I did not check it because I assumed that if the debugger calls the getter after the comparison this was the problem. It turns however that this is the normal behavior.


  2. 0

    I created this structure based on your description and it works

    class AlarmObj {
  isAlarmOn = true
  get getAlarmOnOffStatus() { return this.isAlarmOn; }
}

class ClockObj {
  AlarmObj = new AlarmObj()
  
  constructor() {
    if (this.AlarmObj.getAlarmOnOffStatus === true) {
      console.log('works')
    }
  }
}


new ClockObj()
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