# AUR4106

## Error Message

`AUR4106: The property name needs to be a non-empty string, encountered: {{propertyName}}`

## Description

This error occurs when attempting to hydrate validation rules with invalid property names. Property names must be non-empty strings that correspond to actual properties on the model being validated.

## Common Scenarios

```typescript
// ❌ Wrong: Empty property name
const rules = [{
  property: '',
  rules: [{ name: 'required' }]
}];

// ❌ Wrong: Null/undefined property name
const rules2 = [{
  property: null,
  rules: [{ name: 'required' }]
}];

// ❌ Wrong: Non-string property name
const rules3 = [{
  property: 123,
  rules: [{ name: 'required' }]
}];
```

## Solution

```typescript
// ✅ Correct: Valid property names
const rules = [
  {
    property: 'userName',
    rules: [{ name: 'required' }]
  },
  {
    property: 'email',
    rules: [{ name: 'required' }, { name: 'email' }]
  }
];

validationRules.hydrateRules(rules);
```


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