import {BehaviorSubject} from"rxjs";class MyWeirdoClass { constructor() {} private st: Subject= new BehaviorSubject(null); changeSt(val:boolean){ this.st.next(val); } val(){ this .st.subscribe(res=>{ if (res){ console.log(res); } }) } stStatus() { this.val(); this.changeSt(true); this.val(); this. changeSt(false); this.val(); }}

truetrue

falsetruefalse

this.val();

this.changeSt(true);

this.val();

this.changeSt(false);

this.val();

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