Error map

Avoid mutating a prop directly Vue: [Vue warn]: Avoid mutating a prop directly since the value will be overwritten whenever the parent component re-renders

Vue · layer 1, On your device

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Centre: this error. First ring: errors it is linked with (4). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.

1 · On your device 4 · Application & API
Avoid mutating a prop directly — Vue: [Vue warn]: Avoid mutating a prop directly since the value will be overwritten whenever the parent component re-renders (Vue)Avoid mutat…Failed to resolve component — Vue: [Vue warn]: Failed to resolve component: x (Vue)Failed to resolve c…non-boolean attribute — Warning: Received `true` for a non-boolean attribute `x`. (React)non-boolean attribu…key is not a prop — Warning: `key` is not a prop. Trying to access it will result in `undefined` being returned. (React)key is not a propProperty was accessed during render but is not defined — Vue: [Vue warn]: Property "x" was accessed during render but is not defined on instance (Vue)Property was access…refs on function components — Warning: Function components cannot be given refs. Attempts to access this ref will fail. Did you mean to use React.forwardRef()? (React)refs on function co…Objects are not valid as a React child — Error: Objects are not valid as a React child (React)Objects are not val…Nothing was returned from render — Error: Nothing was returned from render. This usually means a return statement is missing. (React)Nothing was returne…Adjacent JSX elements — Adjacent JSX elements must be wrapped in an enclosing tag. Did you want a JSX fragment <>...</>? (React)Adjacent JSX elemen…unique key prop — Warning: Each child in a list should have a unique "key" prop (React)unique key propuncontrolled to controlled — Warning: A component is changing an uncontrolled input to be controlled (React)uncontrolled to con…IndexError — IndexError: list index out of range (Python)IndexErrorReferenceError — ReferenceError: x is not defined (JavaScript)ReferenceErrorTemplateDoesNotExist — django.template.exceptions.TemplateDoesNotExist: app/page.html (Python)TemplateDoesNotExistNG8002 — Angular: NG8002: Can't bind to 'ngModel' since it isn't a known property of 'input' (Angular)NG8002

Directly related (4)

Failed to resolve componentVue

Vue: [Vue warn]: Failed to resolve component: x

The template uses a component tag that isn’t registered or imported where it’s used.

non-boolean attributeReact

Warning: Received `true` for a non-boolean attribute `x`.

A boolean was passed to a DOM attribute that expects a string, or a custom prop leaked through to a DOM element.

key is not a propReact

Warning: `key` is not a prop. Trying to access it will result in `undefined` being returned.

A component tried to read props.key, which React reserves and never passes down.

Property was accessed during render but is not definedVue

Vue: [Vue warn]: Property "x" was accessed during render but is not defined on instance

The template references a variable/function that the component doesn’t expose.

Two steps away (10)

refs on function componentsReact

Warning: Function components cannot be given refs. Attempts to access this ref will fail. Did you mean to use React.forwardRef()?

A ref was passed to a function component that doesn’t forward it.

Objects are not valid as a React childReact

Error: Objects are not valid as a React child

You tried to render a plain object (or a Promise/Date) directly in JSX; React can only render strings, numbers, elements and arra…

Nothing was returned from renderReact

Error: Nothing was returned from render. This usually means a return statement is missing.

A component returned undefined (React 17 and earlier) — usually a missing return or a return followed by a line break.

Adjacent JSX elementsReact

Adjacent JSX elements must be wrapped in an enclosing tag. Did you want a JSX fragment <>...</>?

A component returns two sibling JSX elements without a single parent.

unique key propReact

Warning: Each child in a list should have a unique "key" prop

When rendering a list with `.map()`, each element needs a stable, unique `key` so React can track items between renders.

uncontrolled to controlledReact

Warning: A component is changing an uncontrolled input to be controlled

An input’s `value` started as `undefined` (uncontrolled) and later became a defined value (controlled), or vice versa.

IndexErrorPython

IndexError: list index out of range

Code accessed a list position that doesn’t exist.

ReferenceErrorJavaScript

ReferenceError: x is not defined

Code refers to a variable or function name that doesn’t exist in the current scope.

TemplateDoesNotExistPython

django.template.exceptions.TemplateDoesNotExist: app/page.html

Django searched all template directories and couldn’t find that template.

NG8002Angular

Angular: NG8002: Can't bind to 'ngModel' since it isn't a known property of 'input'

The template uses a property binding that no imported directive provides — for ngModel, FormsModule isn’t imported.

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