# AUR0153

## Error Message

`AUR0153: Expression error: expected identifier: "{{expression}}"`

## Description

This error occurs when the parser expects an identifier (a variable/property name) but finds something else.

## Example Trigger

```html
<!-- ❌ Missing identifier after dot -->
<div textcontent.bind="user..name"></div>

<!-- ❌ Missing identifier after '|' (value converter) -->
<div textcontent.bind="message |"></div>
```

## Solution

* Ensure property access uses a valid identifier (`obj.prop`).
* Ensure value converters / behaviors specify a name (`value | converter`, `value & behavior`).

## Troubleshooting

* Look at the expression shown in the error and find where an identifier is missing.
* Simplify the expression until it parses, then re-introduce parts.


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