---
title: MARKLESS_COMPONENT_SPREAD_UNSUPPORTED
description: "Only the props rest binding can be spread onto a component: a Markless compiler error."
sidebar: { hidden: true }
search: { keywords: ["COMPONENT_SPREAD_UNSUPPORTED","component spread unsupported","markless error"] }
pagination: false
---

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

## What happened

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

```text
MARKLESS_COMPONENT_SPREAD_UNSUPPORTED: `{...<source>}` on `<<childComponentName>>` cannot be forwarded, because `<source>` is not this component's props rest binding.
What a spread carries onto a child component is decided at build time, from the signature that produced it. An object assembled anywhere else has no build-time contents, so the child would render without the entries and nothing would say so.
Spread the rest binding of this component's own props (`function Part({ known, ...rest })` then `<Child {...rest} />`), or write the props you mean out by name on the tag.
https://markless.dev/errors/MARKLESS_COMPONENT_SPREAD_UNSUPPORTED
```

Words in angle brackets change from case to case.

## How to fix it

Start with the suggestion in the message above.

This page has no guide yet. [Help write it](/contributing/improve-these-docs).

## Where it comes from

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

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

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