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# CallStackTree

A tree structure representing a collection of call stacks captured during a diagnostic event.

```
struct CallStackTree
```

## Discussion

Each diagnostic struct — including [`CrashDiagnostic`](/documentation/MetricKit/CrashDiagnostic), [`HangDiagnostic`](/documentation/MetricKit/HangDiagnostic), [`CPUExceptionDiagnostic`](/documentation/MetricKit/CPUExceptionDiagnostic), [`DiskWriteExceptionDiagnostic`](/documentation/MetricKit/DiskWriteExceptionDiagnostic), [`AppLaunchDiagnostic`](/documentation/MetricKit/AppLaunchDiagnostic), and [`MemoryExceptionDiagnostic`](/documentation/MetricKit/MemoryExceptionDiagnostic) — carries a `callStackTree` property of this type.

The tree is organized into threads via [`callStackThreads`](/documentation/MetricKit/CallStackTree/callStackThreads). Each [`CallStackThread`](/documentation/MetricKit/CallStackThread) contains root [`CallStackFrame`](/documentation/MetricKit/CallStackFrame) values that form a tree of sub-frames. Binary metadata is deduplicated in [`binaryInfo`](/documentation/MetricKit/CallStackTree/binaryInfo-swift.property), keyed by UUID, so frames reference binaries by UUID rather than repeating the name.

Use [`forEachFrame(_:)`](/documentation/MetricKit/CallStackTree/forEachFrame(_:)) for an optimized iterative depth-first traversal of all frames across all threads:

```swift
callStackTree.forEachFrame { frame in
    if let name = frame.binaryName(from: callStackTree) {
        print(name, frame.offsetIntoBinaryTextSegment ?? 0)
    }
}
```

## Topics

### Threads and frames

[`callStackThreads`](/documentation/MetricKit/CallStackTree/callStackThreads)

Array of call stack threads

[`callStackPerThread`](/documentation/MetricKit/CallStackTree/callStackPerThread)

Whether call stacks are organized per-thread

[`forEachFrame(_:)`](/documentation/MetricKit/CallStackTree/forEachFrame(_:))

Iterates all frames efficiently.

### Binary information

[`binaryInfo`](/documentation/MetricKit/CallStackTree/binaryInfo-swift.property)

Deduplicated binary information indexed by UUID

### Related types

[`CallStackThread`](/documentation/MetricKit/CallStackThread)

A single stack thread within a call stack tree.

[`CallStackFrame`](/documentation/MetricKit/CallStackFrame)

A single frame within a call stack thread.


---

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