I am having problem understanding the behavior of below code in JavaScript
.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ height:90px;width:728px;box-sizing:border-box;
}
I was playing with below javascript code. Understanding of Object.defineProperty() and I am facing a strange issue with it. When I try to execute below code in the browser or in the VS code the output is not as expected whereas if I try to debug the code the output is correct
When I debug the code and evaluate the profile I can see the name & age property in the object
But at the time of output, it only shows the name property
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true
})
console.log(profile)
console.log(profile.age)Now expected output here should be
{name: "Barry Allen", age: 23}
23
but I get the output as.
Note that I am able to access the age property defined afterwards.
I am not sure why the console.log() is behaving this way.
{name: "Barry Allen"}
23
javascript
edited 33 mins ago
Eddie
20.3k51642
asked 34 mins ago
Ravi WRavi W
384
New contributor
Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
I was playing with below javascript code. Understanding of Object.defineProperty() and I am facing a strange issue with it. When I try to execute below code in the browser or in the VS code the output is not as expected whereas if I try to debug the code the output is correct
When I debug the code and evaluate the profile I can see the name & age property in the object
But at the time of output, it only shows the name property
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true
})
console.log(profile)
console.log(profile.age)Now expected output here should be
{name: "Barry Allen", age: 23}
23
but I get the output as.
Note that I am able to access the age property defined afterwards.
I am not sure why the console.log() is behaving this way.
{name: "Barry Allen"}
23
javascript
edited 33 mins ago
Eddie
20.3k51642
asked 34 mins ago
Ravi WRavi W
384
New contributor
Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
I was playing with below javascript code. Understanding of Object.defineProperty() and I am facing a strange issue with it. When I try to execute below code in the browser or in the VS code the output is not as expected whereas if I try to debug the code the output is correct
When I debug the code and evaluate the profile I can see the name & age property in the object
But at the time of output, it only shows the name property
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true
})
console.log(profile)
console.log(profile.age)Now expected output here should be
{name: "Barry Allen", age: 23}
23
but I get the output as.
Note that I am able to access the age property defined afterwards.
I am not sure why the console.log() is behaving this way.
{name: "Barry Allen"}
23
javascript
edited 33 mins ago
Eddie
20.3k51642
asked 34 mins ago
Ravi WRavi W
384
New contributor
Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I was playing with below javascript code. Understanding of Object.defineProperty() and I am facing a strange issue with it. When I try to execute below code in the browser or in the VS code the output is not as expected whereas if I try to debug the code the output is correct
When I debug the code and evaluate the profile I can see the name & age property in the object
But at the time of output, it only shows the name property
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true
})
console.log(profile)
console.log(profile.age)Now expected output here should be
{name: "Barry Allen", age: 23}
23
but I get the output as.
Note that I am able to access the age property defined afterwards.
I am not sure why the console.log() is behaving this way.
{name: "Barry Allen"}
23
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true
})
console.log(profile)
console.log(profile.age)//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true
})
console.log(profile)
console.log(profile.age)javascript
javascript
edited 33 mins ago
Eddie
20.3k51642
asked 34 mins ago
Ravi WRavi W
384
New contributor
Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 33 mins ago
Eddie
20.3k51642
asked 34 mins ago
Ravi WRavi W
384
New contributor
Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 33 mins ago
Eddie
20.3k51642
edited 33 mins ago
Eddie
20.3k51642
edited 33 mins ago
Eddie
20.3k51642
20.3k51642
asked 34 mins ago
Ravi WRavi W
384
New contributor
Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 34 mins ago
Ravi WRavi W
384
asked 34 mins ago
Ravi WRavi W
384
384
New contributor
Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Ravi W is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
add a comment |
3 Answers
3
active
oldest
votes
You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.
enumerable
trueif and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile , 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)Example: All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.
To get all properties(including non-enumerable)Object.getOwnPropertyNames()
.
answered 32 mins ago
Maheer AliMaheer Ali
11.5k826
I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifyingenumerableto false).
– randomSoul
21 mins ago
@randomSoul I can't get what you mean.
– Maheer Ali
16 mins ago
See - pasteboard.co/IaOxMqB.png . I did not setenumerableto true forage, but still it is shown.
– randomSoul
10 mins ago
add a comment |
By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you console.log them, nor when you iterate over their Object.keys. (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)
See MDN:
enumerable
true if and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Make it enumerable instead:
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)answered 31 mins ago
CertainPerformanceCertainPerformance
101k166291
add a comment |
Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable : true,
configurable : true
})
console.log(profile)
console.log(profile.age)
answered 28 mins ago
RK_15RK_15
5749
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.
enumerable
trueif and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile , 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)Example: All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.
To get all properties(including non-enumerable)Object.getOwnPropertyNames()
.
answered 32 mins ago
Maheer AliMaheer Ali
11.5k826
I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifyingenumerableto false).
– randomSoul
21 mins ago
@randomSoul I can't get what you mean.
– Maheer Ali
16 mins ago
See - pasteboard.co/IaOxMqB.png . I did not setenumerableto true forage, but still it is shown.
– randomSoul
10 mins ago
add a comment |
You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.
enumerable
trueif and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile , 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)Example: All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.
To get all properties(including non-enumerable)Object.getOwnPropertyNames()
.
answered 32 mins ago
Maheer AliMaheer Ali
11.5k826
I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifyingenumerableto false).
– randomSoul
21 mins ago
@randomSoul I can't get what you mean.
– Maheer Ali
16 mins ago
See - pasteboard.co/IaOxMqB.png . I did not setenumerableto true forage, but still it is shown.
– randomSoul
10 mins ago
add a comment |
You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.
enumerable
trueif and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile , 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)Example: All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.
To get all properties(including non-enumerable)Object.getOwnPropertyNames()
.
answered 32 mins ago
Maheer AliMaheer Ali
11.5k826
You should set enumerable to true. In Object.defineProperty its false by default. According to MDN.
enumerable
trueif and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Non-enumerable means that property will not be shown in Object.keys() or for..in loop neither in console
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile , 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)Example: All the properties and methods on prototype object of built-in classes are non-enumerable. Thats is the reason you can call them from instance but they don't appear while iterating.
To get all properties(including non-enumerable)Object.getOwnPropertyNames()
.
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile , 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile , 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)answered 32 mins ago
Maheer AliMaheer Ali
11.5k826
edited 10 mins ago
answered 32 mins ago
Maheer AliMaheer Ali
11.5k826
answered 32 mins ago
Maheer AliMaheer Ali
11.5k826
answered 32 mins ago
Maheer AliMaheer Ali
11.5k826
11.5k826
I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifyingenumerableto false).
– randomSoul
21 mins ago
@randomSoul I can't get what you mean.
– Maheer Ali
16 mins ago
See - pasteboard.co/IaOxMqB.png . I did not setenumerableto true forage, but still it is shown.
– randomSoul
10 mins ago
add a comment |
I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifyingenumerableto false).
– randomSoul
21 mins ago
@randomSoul I can't get what you mean.
– Maheer Ali
16 mins ago
See - pasteboard.co/IaOxMqB.png . I did not setenumerableto true forage, but still it is shown.
– randomSoul
10 mins ago
I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifying
enumerable to false).– randomSoul
21 mins ago
I didn't knew about this, but when I checked by running the local code in browser, it shows up perfectly (in spite of explicitly specifying
enumerable to false).– randomSoul
21 mins ago
@randomSoul I can't get what you mean.
– Maheer Ali
16 mins ago
@randomSoul I can't get what you mean.
– Maheer Ali
16 mins ago
See - pasteboard.co/IaOxMqB.png . I did not set
enumerable to true for age, but still it is shown.– randomSoul
10 mins ago
See - pasteboard.co/IaOxMqB.png . I did not set
enumerable to true for age, but still it is shown.– randomSoul
10 mins ago
add a comment |
By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you console.log them, nor when you iterate over their Object.keys. (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)
See MDN:
enumerable
true if and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Make it enumerable instead:
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)answered 31 mins ago
CertainPerformanceCertainPerformance
101k166291
add a comment |
By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you console.log them, nor when you iterate over their Object.keys. (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)
See MDN:
enumerable
true if and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Make it enumerable instead:
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)answered 31 mins ago
CertainPerformanceCertainPerformance
101k166291
add a comment |
By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you console.log them, nor when you iterate over their Object.keys. (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)
See MDN:
enumerable
true if and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Make it enumerable instead:
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)answered 31 mins ago
CertainPerformanceCertainPerformance
101k166291
By default, properties you define with defineProperty are not enumerable - this means that they will not show up when you console.log them, nor when you iterate over their Object.keys. (Similarly, the length property of an array does not get displayed, because it's non-enumerable.)
See MDN:
enumerable
true if and only if this property shows up during enumeration of the properties on the corresponding object.
Defaults to false.
Make it enumerable instead:
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable: true
})
console.log(profile)
console.log(profile.age)answered 31 mins ago
CertainPerformanceCertainPerformance
101k166291
answered 31 mins ago
CertainPerformanceCertainPerformance
101k166291
answered 31 mins ago
CertainPerformanceCertainPerformance
101k166291
answered 31 mins ago
CertainPerformanceCertainPerformance
101k166291
101k166291
add a comment |
add a comment |
Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable : true,
configurable : true
})
console.log(profile)
console.log(profile.age)
answered 28 mins ago
RK_15RK_15
5749
add a comment |
Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable : true,
configurable : true
})
console.log(profile)
console.log(profile.age)
answered 28 mins ago
RK_15RK_15
5749
add a comment |
Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable : true,
configurable : true
})
console.log(profile)
console.log(profile.age)
answered 28 mins ago
RK_15RK_15
5749
Whenever you use".defineProperty" method of object. You should better define all the properties of the descriptor. Because if you don't define other property descriptor then it assumes default values for all of them which is false. So your console.log checks for all the enumerable : true properties and logs them.
//Code Snippet
let profile = {
name: 'Barry Allen',
}
// I added a new property in the profile object.
Object.defineProperty(profile, 'age', {
value: 23,
writable: true,
enumerable : true,
configurable : true
})
console.log(profile)
console.log(profile.age)
answered 28 mins ago
RK_15RK_15
5749
answered 28 mins ago
RK_15RK_15
5749
answered 28 mins ago
RK_15RK_15
5749
answered 28 mins ago
RK_15RK_15
5749
5749
add a comment |
add a comment |
Ravi W is a new contributor. Be nice, and check out our Code of Conduct.
Ravi W is a new contributor. Be nice, and check out our Code of Conduct.
Ravi W is a new contributor. Be nice, and check out our Code of Conduct.
Ravi W is a new contributor. Be nice, and check out our Code of Conduct.
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