How does the js object gracefully take a depth value?

problem description

for example, the background may return an object 

let obj = {
    school: {
      class1: {
        student: 50
      }
    }
}

I need to take out the value of student in it, but it is possible that {school: null} or {} or even undefined

is returned to me by the background.

so when I take a value, it may be 

let student = obj?(obj.school?(obj.school.class1?(obj.school.class1.studnet?obj.school.class1.studnet:""):""):""):"";

this is obviously not readable and troublesome. Is there any way to deal with this value gracefully

and prevent Cannot read property "xxx" of undefined from reporting errors

Javascript
Nov.26,2021 
function safeProps(func, defaultVal) {
    try {
        return func();
    } catch (e) {
        return defaultVal;
    }
}

safeProps(function(){
    student = obj.school.class1.student
}, -1)

adding Proxy listening get is a very appropriate method if compatibility is not considered. 

/**
 * @param target
 * @param exec 
 * @returns {*}
 */
function getter(target, exec = '_') {
  return new Proxy({}, {
    get: (o, n) => {
      return n === exec ?
        target :
        getter(typeof target === 'undefined' ? target : target[n], exec)
    }
  });
}
let obj = {
  school: {
    class1: {
      student: 50
    }
  }
};

console.log(getter(obj).school.class1.student._)//50
console.log(getter(obj).school1.class11.student._)//undefined

lodash/get find out, _ .get (obj,'school.class1.student', undefined), lodash/get

Hello, landlord! You can use the following methods to do defensive programming . 

  
 if it were me, I would do this. Let student = obj&&obj.school&obj.school.class1&&obj.school.class1.student 
 I hope it will be helpful to you

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MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1e59cb9-44293.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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Message : Disk full (/tmp/#sql-temptable-64f5-1e59cb9-44293.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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