# Swift: Reference to property 'x' in closure requires explicit use of 'self' to make capture semantics explicit

**Code:** `requires explicit use of 'self'` · **Category:** iOS · **Seen on:** iOS

In an escaping closure inside a class, Swift requires self. to make the capture (and potential retain cycle) visible.

## Meaning

Add self. or capture [weak self] / [self] explicitly. For long-lived closures prefer [weak self] to avoid retain cycles.

## Common causes

- Escaping closure referencing instance properties without self
- Copying code from SwiftUI structs into classes

## Quick fix

1. Write self.property
2. Use [weak self] and guard let self
3. Use [self] capture list when a strong capture is intended

## Detailed fix by platform

### Swift

1. 

```swift
api.load { [weak self] result in
    guard let self else { return }
    self.items = result
}
```


## How to diagnose

1. **Closure** — Escaping and long-lived?
2. **Cycle** — Does self own the closure?

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Source: [WhatIsMyError](https://whatismyerror.com/errors/ios/reference-to-property-requires-explicit-self)