Tag: undefined

Javascript `?.` operator: why is `not defined` not treated as `undefined`?

Assuming w has not been previously defined, the following JS code gives ReferenceError: w is not defined: whereas this code simply returns undefined: Why does the ?. operator not treat not defined as undefined? Answer This is mentioned in the documentation Optional chaining cannot be used on a non-declared root object, but can be used with an undefined root object.

How to force a type in a variable : The property does not exist in the type ‘AllMatch | SingleMatch’ ts(2339)

javascript typechecking types typescript undefined

I have an interface of this shape: And I need to access the value field of the SingleMatch interface on a variable. To do this I use the following code: In the buildMonoExpressionSingleMatch() function I can access my variable without error if I check before that the function is of the right type for index 0: But if I do

Uncaught TypeError: Cannot read properties of undefined (reading ‘replace’). I am facing this error in my site

javascript replace typeerror undefined wordpress

I am using this code on the WordPress website and errors continuously coming to my site. This picture shows the error Answer The reason why you are receiving this error is because the variable valor does not have a value assigned to it and thus is undefined. replace() is a function that acts on string values. PROBLEM: Solution 1: To

How to drop null elements but not undefined when using `arr.flatMap((f) => f ?? [])`?

javascript null typescript undefined

I’ve written a function that removes null values from an array: For example: However, I realized that it also removes undefined values. Is there a way to just tweak the current dropNull() in order to remove null but not undefined? That is, I know I could have re-written the function as: But I like the arr.flatMap((f) => f ?? [])

Cannot Read Property “toString” of Undefined – Javascript [closed]

arrays javascript tostring undefined

Closed. This question is not reproducible or was caused by typos. It is not currently accepting answers. This question was caused by a typo or a problem that can no longer be reproduced. While similar questions may be on-topic here, this one was resolved in a way less likely to help future readers. Closed 1 year ago. Improve this question

Undefined when i am returning an Object in Javascript

javascript return undefined vue.js vuex

I’m doing a getter in VueX, and when i’m returning an object for another function, i have “undefined”. Basically i have a function like that. When i’m showing obj with console.log(obj), i have an object with elements in here. And basically it’s working. But when i’m doing a return and i’m trying to get the obj in another function I

Why am i getting ‘undefined’ from this JSON object? [closed]

javascript undefined

.click() on hidden input button doesn’t work (undefined)

click javascript jquery undefined wordpress

I’ve spent hours and read countless stackoverflows but I can’t get this to work. I’ve got a form (Caldera Form in Wordpress) that has a submit button (in fact it’s an input tag). Via JS I added an event listener because I want to make a backup of the form data to my database. The event listener line: The handleIorSaveClick

Im getting an error in my react and rest api app where one of my variables is coming back undefined

javascript react-fullstack reactjs rest undefined

thank you for your time if youre reading this, im making a full stack app with react and rest api and im encountering an error as such: the part where this error is throwing is right here: heres my createUser function code: heres the code handiling post / users Im really not sure whats going on with my errors variable

ES6 modules – imported constants undefined if not in React component

ecmascript-6 es6-modules javascript reactjs undefined

The only similar question I have found is this one but I can’t see how would I have caused a circular dependancy in this case: I have a file exporting constants like so: (choices array version is for using in Select inputs and the other one secures from typing errors in condition checks) payments.constants.js When they are imported inside any