---
title: "invalid_unicode: error reference · tabnas"
description: "The tabnas engine error code invalid_unicode: message, diagnostic details, and recovery steps."
source: "https://tabnas.dev/errors/invalid_unicode/"
---

[Error reference](https://tabnas.dev/errors/)

# `invalid_unicode`

Raised by the parsing engine, so any grammar can produce it.

## Message

```
invalid unicode escape: {src}
```

## Hint

```
The escape sequence {src} does not encode a valid unicode code point.
```

`{placeholders}` are filled from the failing token and the details the grammar attached. The wording is informative and can change between releases: **the code is the contract**. It is what both the TypeScript and Go runtimes guarantee.

## What to do with it

1.  Read the rest of the diagnostic: `row`/`col` point at the input, `expected` lists the tokens that would have matched, and `ruleStack` shows how the parser got there.
2.  Reproduce it on its own with `tabnas diagnose --json`, which prints the whole object.
3.  Work the grammar back from the failing alternate: the [`debug-parse` skill](https://tabnas.dev/skills/) is that procedure written out, and [the errors guide](https://tabnas.dev/how-to/parse-errors/) covers raising good ones from your own grammar.

Generated from [the engine's error registry](https://github.com/tabnas/parser/blob/main/schema/error-codes.json). Engine 0.12.9.