# AUR0159

## Error Message

`AUR0159: Expression error: expected identifier to come after value converter operator: "{{expression}}"`

## Description

This error occurs when a value converter operator (`|`) is used without providing a converter name.

## Example Trigger

```html
<!-- ❌ Missing converter name -->
<div textcontent.bind="message |"></div>
<div textcontent.bind="count | :arg"></div>
```

## Solution

Provide a value converter name after `|`.

```html
<!-- ✅ -->
<div textcontent.bind="message | upper"></div>
<div textcontent.bind="count | numberFormat:'en-US'"></div>
```

## Troubleshooting

* Check for trailing `|` in expressions.
* Ensure the converter is registered (otherwise you may get a different error during evaluation).


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