Re: A way to prevent properties to be added to an object if they are null or undefined.

Tue, 28 Nov 2017 17:46:28 -0800

So something like the following?


```js
a.field ?= value;
```

And this sets the property `field` of object `a` to `value` if `value != null`.

Sebastian Malton

Sent: November 28, 2017 8:40 PM
Subject: Re: A way to prevent properties to be added to an object if they are null or undefined.

It's about the value of the property to be added, nothing to do with the name of the property. It should discard properties whose value are null(but this behavior is not always desired, so a different syntax for these properties should be added).

```

On nov. 28 2017, at 8:33 pm, Sebastian Malton <[email protected]> wrote:
I am sort of confused about what you are asking, is the check about the property name or the current value of the property? 

Sebastian Malton

Sent: November 28, 2017 8:30 PM
Subject: A way to prevent properties to be added to an object if they are null or undefined.

A way to prevent properties to be added to an object if they are null or undefined.

Currently this can be accomplished in many ways:

With an if:
```js
function foo(couldBeNull){
let ret = {}
if(couldBeNull){
ret.couldBeNull = couldBeNull
}
return  ret
}
```

With ternary (kind of gross)
```js
function foo(couldBeNull){
let ret = {}
couldBeNull ? (ret.couldBeNull = couldBeNull) : null
return  ret
}
```

Also gross
```js
function foo(couldBeNull){
let ret = {}
couldBeNull && (ret.couldBeNull = couldBeNull) 
return  ret
}
```

A bit hard to read:
```js
function foo(couldBeNull){
let ret = {
...({couldBeNull} : {})
}
return  ret
}
```

Requires importing a lib or writing the function by yourself. Also it has to iterate over all values
```js
function foo(couldBeNull){
let ret = {
couldBeNull
}
ret = removeEmptyValues(ret) // imported from some library
return  ret
}
```

Wouldn't it be better something like this?:

```js
function foo(couldBeNull){
let ret = {
couldBeNull?
}
return  ret
}
```

Or if you want to set other property name

```js
function foo(couldBeNull){
let ret = {
bar ?:  couldBeNull // bar is not added if couldBeNull is null or undefined
}
return  ret
}
```

Libre de virus. www.avast.com
_______________________________________________
es-discuss mailing list
[email protected]
https://mail.mozilla.org/listinfo/es-discuss
_______________________________________________
es-discuss mailing list
[email protected]
https://mail.mozilla.org/listinfo/es-discuss

Reply via email to