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# PHASEDefinition

A base class that adds a name to framework definitions.

```
class PHASEDefinition
```

## Overview

Various PHASE classes derive from this class, for example, [`PHASEMixerDefinition`](/documentation/PHASE/PHASEMixerDefinition), [`PHASEMetaParameterDefinition`](/documentation/PHASE/PHASEMetaParameterDefinition), and [`PHASESoundEventNodeDefinition`](/documentation/PHASE/PHASESoundEventNodeDefinition).

This class represents a template from which PHASE creates concrete [`PHASEAsset`](/documentation/PHASE/PHASEAsset) subclasses at runtime. For example, when you register a global metaparameter definition using [`registerGlobalMetaParameter(metaParameterDefinition:)`](/documentation/PHASE/PHASEAssetRegistry/registerGlobalMetaParameter(metaParameterDefinition:)), PHASE returns a [`PHASEAsset`](/documentation/PHASE/PHASEAsset) subclass, [`PHASEGlobalMetaParameterAsset`](/documentation/PHASE/PHASEGlobalMetaParameterAsset), that identifies a usable metaparameter by name. To access the usable metaparameter, pass the [`PHASEGlobalMetaParameterAsset`](/documentation/PHASE/PHASEGlobalMetaParameterAsset) [`identifier`](/documentation/PHASE/PHASEAsset/identifier) into the [`globalMetaParameters`](/documentation/PHASE/PHASEAssetRegistry/globalMetaParameters) dictionary.

## Topics

### Identifying a Definition

[`identifier`](/documentation/PHASE/PHASEDefinition/identifier)

A unique name for the definition.

## Relationships

### Conforms To

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Hashable`](/documentation/Swift/Hashable)

[`Equatable`](/documentation/Swift/Equatable)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CVarArg`](/documentation/Swift/CVarArg)

### Inherited By

[`PHASEMetaParameterDefinition`](/documentation/PHASE/PHASEMetaParameterDefinition)

[`PHASESoundEventNodeDefinition`](/documentation/PHASE/PHASESoundEventNodeDefinition)

[`PHASEMixerDefinition`](/documentation/PHASE/PHASEMixerDefinition)

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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