---
title: MARKLESS_STATE_READ_ONLY_WRITE
description: "Code writes to a computed() value or to a prop, and both are read-only."
sidebar: { hidden: true }
search: { keywords: ["STATE_READ_ONLY_WRITE","state read only write","markless error"] }
pagination: false
---

**Error** from the compiler, while it builds your `.tsrx` files.

## What happened

You can only write to `state()`. A `computed()` value and a prop are read-only.

Markless prints the message, the reason, and a suggestion:

```text
MARKLESS_STATE_READ_ONLY_WRITE: Cannot write to "<target>" because <bindingLabel> are read-only.
https://markless.dev/errors/MARKLESS_STATE_READ_ONLY_WRITE
```

Words in angle brackets change from case to case.

## How to fix it

For a computed value, write to the state it reads from. For a prop, let the parent own the state, and pass down a handler that changes it.

## Where it comes from

`@markless/compiler` raises this code. Source:

- [packages/compiler/src/passes/state-lowering.ts](https://github.com/compiled-run/markless/blob/main/packages/compiler/src/passes/state-lowering.ts)

Read [how to read a Markless error](/tooling/diagnostics), or go back to [all error codes](/errors).