ChatGPTでソースコードをPlantUMLに変換してクラス図からVerse APIを理解する

こんにちは、Unity/Unrealエンジニアの[イワケン](https://twitter.com/iwaken71)です。
最近はUEFNを楽しんでいます。

VerseのAPIを理解するために、クラスの依存関係や継承関係を可視化できたら...!という思いでこの記事を書きました。

前回の記事でもVerseのソースコードをクラス図にして理解を進めました。それのやり方を共有します。

https://qiita.com/iwaken71/items/c118737da5cb0ff38f54

![image.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/96970/42f70709-70ba-d454-3a94-642052a69f74.png)

# 前提

- ChatGPTのGPT4が使える
- UEFNからVisual Studio Codeが使える
- PlantUMLが多少理解できている

# 今回のゴール

- VerseのUI実装のクラス図の関係をPlantUMLで画像として書き出す

# やったこと

- Visual Studio Code
    - UnrealEngine.digest.verseなどを開き、調べたいコードが書かれているファイルを開く
    - ソースコードをコピペする
- ChatGPT
    - ソースコードを元にプロンプトでPlantUMLのコードを聞き出す
- Qiita
    - PlantUMLのコードを画像に変換する
    - これは何でもよい
    - Visual Studio CodeからもPlantUML化は可能
        - [PlantUMLでクラス図を作成](https://www.wakuwakubank.com/posts/565-design-uml-class/)


## UnrealEngine.digest.verseなどを開き、調べたいコードが書かれているファイルを開く

![image.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/96970/9d1432ab-52cb-04a2-0f49-8b4f62c3b528.png)

## ソースコードをコピペする

今回はUIモジュールの中のみにする。実際コピペしたコードは、記事の最後のおまけに掲載しています。

![image.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/96970/08ce0af2-d1b1-9a39-27e3-447025f1d45f.png)

## ChatGPT「ソースコードを元にプロンプトでPlantUMLのコードを聞き出す」

以下のプロンプト
```text:Prompt①
以下のソースコードを
#のコメント部分をなくした文字列にしてください

===
{ソースコードをコピペ}
```

```text:Prompt②
上記のソースコードから
PlantUMLを使ってクラス図を作りたいです。
例えば
canvasとwidgetクラスについて以下のように書けます。
残りのクラスについても書いてください。日本語でお願いします。

===
@startuml

widget <- player_ui
widget <|-- canvas

abstract class widget {
  # field
  --
  # SetVisibility(widget_visibility)
  # GetVisibility():widget_visibility
  # SetEnabled(logic)
  # IsEnabled():logic
  # GetParentWidget():widget
  # GetRootWidget():widget
}

class player_ui {
  # AddWidget(widget)
  # RemoveWidget(widget)
}


@enduml
===
```

## 出力されたPlantUMLのコード

```plaintext
@startuml

widget <|-- button
widget <|-- canvas
widget <|-- color_block
widget <|-- texture_block
widget <|-- overlay
widget <|-- stack_box
widget <|-- text_base

abstract class widget {
    --
    # SetVisibility(widget_visibility)
    # GetVisibility():widget_visibility
    # SetEnabled(logic)
    # IsEnabled():logic
    # GetParentWidget():widget
    # GetRootWidget():widget
}

class player_ui {
    --
    # AddWidget(widget)
    # AddWidget(widget, player_ui_slot)
    # RemoveWidget(widget)
}

class button {
    # Slot:button_slot
    --
    # SetWidget(button_slot)
}

class canvas {
    # Slots:[]canvas_slot
    --
    # AddWidget(canvas_slot)
    # RemoveWidget(widget)
}

class color_block {
    # DefaultColor:color
    # DefaultOpacity:float
    # DefaultDesiredSize:vector2
    --
    # SetColor(color)
    # GetColor():color
    # SetOpacity(float)
    # GetOpacity():float
    # SetDesiredSize(vector2)
    # GetDesiredSize():vector2
}

class texture_block {
    # DefaultImage:texture
    --
    # SetImage(texture)
    # GetImage():texture
    # SetTint(color)
    # GetTint():color
    # SetDesiredSize(vector2)
    # GetDesiredSize():vector2
    # SetTiling(image_tiling, image_tiling)
    # GetTiling():tuple
}

class overlay {
    # Slots:[]overlay_slot
    --
    # AddWidget(overlay_slot)
    # RemoveWidget(widget)
}

class stack_box {
    # Slots:[]stack_box_slot
    # Orientation:orientation
    --
    # AddWidget(stack_box_slot)
    # RemoveWidget(widget)
}

abstract class text_base {
    # DefaultText:message
    # DefaultTextColor:color
    # DefaultTextOpacity:float
    # DefaultJustification:text_justification
    # DefaultOverflowPolicy:text_overflow_policy
    --
    # SetText(message)
    # GetText():[]char
    # SetJustification(text_justification)
    # GetJustification():text_justification
    # SetOverflowPolicy(text_overflow_policy)
    # GetOverflowPolicy():text_overflow_policy
    # SetTextColor(color)
    # GetTextColor():color
    # SetTextOpacity(float)
    # GetTextOpacity():float
}

@enduml


```

# QiitaでPlantUMLで図に変換

「```plantuml
hogehoge
` ``」


とソースコードを囲うとUML図を出力してくれます。 (閉じる方はあえて、スペースをを空けています。「`」を3つ並べるのが正しい書き方です。

```plantuml

@startuml

widget <|-- button
widget <|-- canvas
widget <|-- color_block
widget <|-- texture_block
widget <|-- overlay
widget <|-- stack_box
widget <|-- text_base

abstract class widget {
    --
    # SetVisibility(widget_visibility)
    # GetVisibility():widget_visibility
    # SetEnabled(logic)
    # IsEnabled():logic
    # GetParentWidget():widget
    # GetRootWidget():widget
}

class player_ui {
    --
    # AddWidget(widget)
    # AddWidget(widget, player_ui_slot)
    # RemoveWidget(widget)
}

class button {
    # Slot:button_slot
    --
    # SetWidget(button_slot)
}

class canvas {
    # Slots:[]canvas_slot
    --
    # AddWidget(canvas_slot)
    # RemoveWidget(widget)
}

class color_block {
    # DefaultColor:color
    # DefaultOpacity:float
    # DefaultDesiredSize:vector2
    --
    # SetColor(color)
    # GetColor():color
    # SetOpacity(float)
    # GetOpacity():float
    # SetDesiredSize(vector2)
    # GetDesiredSize():vector2
}

class texture_block {
    # DefaultImage:texture
    --
    # SetImage(texture)
    # GetImage():texture
    # SetTint(color)
    # GetTint():color
    # SetDesiredSize(vector2)
    # GetDesiredSize():vector2
    # SetTiling(image_tiling, image_tiling)
    # GetTiling():tuple
}

class overlay {
    # Slots:[]overlay_slot
    --
    # AddWidget(overlay_slot)
    # RemoveWidget(widget)
}

class stack_box {
    # Slots:[]stack_box_slot
    # Orientation:orientation
    --
    # AddWidget(stack_box_slot)
    # RemoveWidget(widget)
}

abstract class text_base {
    # DefaultText:message
    # DefaultTextColor:color
    # DefaultTextOpacity:float
    # DefaultJustification:text_justification
    # DefaultOverflowPolicy:text_overflow_policy
    --
    # SetText(message)
    # GetText():[]char
    # SetJustification(text_justification)
    # GetJustification():text_justification
    # SetOverflowPolicy(text_overflow_policy)
    # GetOverflowPolicy():text_overflow_policy
    # SetTextColor(color)
    # GetTextColor():color
    # SetTextOpacity(float)
    # GetTextOpacity():float
}

@enduml


```

## 実際のコードを見ながら微修正

継承関係や依存関係など見ながら、足りていないところなどを追加します。

こちらの記事を参考にしてみます。

https://www.wakuwakubank.com/posts/565-design-uml-class/

例えば
- 継承
    - `<|-` 横に配置
    - `<|--` 縦に配置
- Interfaceの実装
    - `<|..`
- 依存
    - `<-`
    - `<..`


今回はこちらを追加。
```
widget <- player_ui
```

今回の最終系はこちら


```plantuml

@startuml

widget <- player_ui
widget <|-- button
widget <|-- canvas
widget <|-- color_block
widget <|-- texture_block
widget <|-- overlay
widget <|-- stack_box
widget <|-- text_base

abstract class widget {
    --
    # SetVisibility(widget_visibility)
    # GetVisibility():widget_visibility
    # SetEnabled(logic)
    # IsEnabled():logic
    # GetParentWidget():widget
    # GetRootWidget():widget
}

class player_ui {
    --
    # AddWidget(widget)
    # AddWidget(widget, player_ui_slot)
    # RemoveWidget(widget)
}

class button {
    # Slot:button_slot
    --
    # SetWidget(button_slot)
}

class canvas {
    # Slots:[]canvas_slot
    --
    # AddWidget(canvas_slot)
    # RemoveWidget(widget)
}

class color_block {
    # DefaultColor:color
    # DefaultOpacity:float
    # DefaultDesiredSize:vector2
    --
    # SetColor(color)
    # GetColor():color
    # SetOpacity(float)
    # GetOpacity():float
    # SetDesiredSize(vector2)
    # GetDesiredSize():vector2
}

class texture_block {
    # DefaultImage:texture
    --
    # SetImage(texture)
    # GetImage():texture
    # SetTint(color)
    # GetTint():color
    # SetDesiredSize(vector2)
    # GetDesiredSize():vector2
    # SetTiling(image_tiling, image_tiling)
    # GetTiling():tuple
}

class overlay {
    # Slots:[]overlay_slot
    --
    # AddWidget(overlay_slot)
    # RemoveWidget(widget)
}

class stack_box {
    # Slots:[]stack_box_slot
    # Orientation:orientation
    --
    # AddWidget(stack_box_slot)
    # RemoveWidget(widget)
}

abstract class text_base {
    # DefaultText:message
    # DefaultTextColor:color
    # DefaultTextOpacity:float
    # DefaultJustification:text_justification
    # DefaultOverflowPolicy:text_overflow_policy
    --
    # SetText(message)
    # GetText():[]char
    # SetJustification(text_justification)
    # GetJustification():text_justification
    # SetOverflowPolicy(text_overflow_policy)
    # GetOverflowPolicy():text_overflow_policy
    # SetTextColor(color)
    # GetTextColor():color
    # SetTextOpacity(float)
    # GetTextOpacity():float
}

@enduml


```

# まとめ

Verse APIを理解するために、依存関係や継承関係を可視化することは有効かもしれません。ぜひ参考にしてみたください。

# 参考記事

- [Visual Studio Code で UML を描こう！](https://qiita.com/couzie/items/9dedb834c5aff09ea7b2)
- [PlantUMLでクラス図を作成](https://www.wakuwakubank.com/posts/565-design-uml-class/)


# おまけ

今回元となったソースコード `UnrealEngine.digest.verse`の一部のUI部分のコードを採用。

```python:UnrealEngine.digest.verse
UI<public> := module:
        # Returns the `player_ui` component associated with `Player`.
        # Fails if there is no `player_ui` associated with `Player`.
        GetPlayerUI<native><public>(Player:player)<transacts><decides>:player_ui

        # The main interface for adding and removing `widget`s to a player's UI.
        player_ui<native><public> := class<final><epic_internal>:
            # Adds `Widget` to this `player_ui` using default `player_ui_slot` configuration options.
            AddWidget<native><public>(Widget:widget):void

            # Adds `Widget` to this `player_ui` using `Slot` for configuration options.
            AddWidget<native><public>(Widget:widget, Slot:player_ui_slot):void

            # Removes `Widget` from this `player_ui`.
            RemoveWidget<native><public>(Widget:widget):void

        # Base class for all UI elements drawn on the `player`'s screen.
        widget<native><public> := class<abstract><unique><epic_internal>:
            # Shows or hides the `widget` without removing itself from the containing `player_ui`.
            # See `widget_visibility` for details.
            SetVisibility<native><public>(InVisibility:widget_visibility):void

            # Returns the current `widget_visibility` state.
            GetVisibility<native><public>():widget_visibility

            # Enables or disables whether the `player` can interact with this `widget`.
            SetEnabled<native><public>(InIsEnabled:logic):void

            # `true` if this `widget` can be modified interactively by the player.
            IsEnabled<native><public>():logic

            # Returns the `widget`'s parent `widget`.
            # Fails if no parent exists, such as if this `widget` is not in the `player_ui` or is itself the root `widget`.
            GetParentWidget<native><public>()<transacts><decides>:widget

            # Returns the `widget` that added this `widget` to the `player_ui`. The root `widget` will return itself.
            # Fails if this `widget` is not in the `player_ui`.
            GetRootWidget<native><public>()<transacts><decides>:widget

        # `widget` creation configuration options.
        player_ui_slot<native><public> := struct:
            # Controls `widget` rendering order. Greater values will be draw in front of lesser values.
            ZOrder<native><public>:type {_X:int where 0 <= _X, _X <= 2147483647} = external {}

            # Controls `widget` input event consumption.
            InputMode<native><public>:ui_input_mode = external {}

        # `widget` input consumption mode.
        ui_input_mode<native><public> := enum:
            # `widget` does not consume any input.
            None
            # `widget` consumes all inputs
            All

        # Parameters for `event`s signalled by a `widget`.
        widget_message<native><public> := struct:
            # The `player` that triggered the `event`.
            Player<native><public>:player

            # The `widget` that triggered the `event`.
            Source<native><public>:widget

        # Used by `widget.SetVisibility` determine how a `widget` is shown in the user interface.
        widget_visibility<native><public> := enum:
            # The `widget` is visible and occupies layout space.
            Visible
            # The `widget` is invisible and does not occupy layout space.
            Collapsed
            # The `widget` is invisible and occupies layout space.
            Hidden

        # Used by`widget` orientation modes.
        orientation<native><public> := enum:
            # Orient `widget`s from left to right.
            Horizontal
            # Orient `widget`s from top to bottom.
            Vertical

        # `widget` horizontal alignment mode.
        horizontal_alignment<native><public> := enum:
            # Center `widget` horizontally within the slot.
            Center
            # Align `widget` to the left of the slot.
            Left
            # Align `widget` to the right of the slot.
            Right
            # `widget` fills the slot horizontally.
            Fill

        # `widget` vertical alignment mode.
        vertical_alignment<native><public> := enum:
            # Center `widget` vertically within the slot.
            Center
            # Align `widget` to the top of the slot.
            Top
            # Align `widget` to the bottom of the slot.
            Bottom
            # `widget` fills the slot vertically.
            Fill

        # The anchors of a `widget` determine its the position and sizing relative to its parent.
        # `anchor`s range from `(0.0, 0.0)` (left, top) to `(1.0, 1.0)` (right, bottom).
        anchors<native><public> := struct:
            # Holds the minimum anchors, (left, top). The valid range is between `0.0` and `1.0`.
            Minimum<native><public>:vector2 = external {}

            # Holds the maximum anchors, (right, bottom). The valid range is between `0.0` and `1.0`.
            Maximum<native><public>:vector2 = external {}

        # Specifies the gap outside each edge separating a `widget` from its neighbors.
        # Distance is measured in units where `1.0` unit is the width of a pixel at 1080p resolution.
        margin<native><public> := struct:
            # The left edge spacing.
            Left<native><public>:float = external {}

            # The top edge spacing.
            Top<native><public>:float = external {}

            # The right edge spacing.
            Right<native><public>:float = external {}

            # The bottom edge spacing.
            Bottom<native><public>:float = external {}

        # Button is a container of a single child widget slot and fires the OnClick event when the button is clicked.
        button<native><public> := class<final>(widget):
            # The child widget of the button. Used only during initialization of the widget and not modified by SetSlot.
            Slot<native><public>:button_slot

            # Sets the child widget slot.
            SetWidget<native><public>(InSlot:button_slot):void

            # Subscribable event that fires when the button is clicked.
            OnClick<public>():listenable(widget_message) = external {}

        # Slot for button widget.
        button_slot<native><public> := struct:
            # The widget assigned to this slot.
            Widget<native><public>:widget

            # Horizontal alignment of the widget inside the slot.
            HorizontalAlignment<native><public>:horizontal_alignment = external {}

            # Vertical alignment of the widget inside the slot.
            VerticalAlignment<native><public>:vertical_alignment = external {}

            # Empty distance in pixels that surrounds the widget inside the slot. Assumes 1080p resolution.
            Padding<native><public>:margin = external {}

        # Canvas is a container widget that allows for arbitrary positioning of widgets in the canvas' slots.
        canvas<native><public> := class<final>(widget):
            # The child widgets of the canvas. Used only during initialization of the widget and not modified by Add/RemoveWidget.
            Slots<native><public>:[]canvas_slot = external {}

            # Adds a new child slot to the canvas.
            AddWidget<native><public>(Slot:canvas_slot):void

            # Removes a slot containing the given widget.
            RemoveWidget<native><public>(Widget:widget):void

        # Slot for a canvas widget.
        canvas_slot<native><public> := struct:
            # The border for the margin and how the widget is resized with its parent.
            # Values are defined between 0.0 and 1.0.
            Anchors<native><public>:anchors = external {}

            # The offset that defined the size and position of the widget.
            # When the anchors are well defined, the Offsets.Left represent the distance in pixels from the Anchors Minimum.X, the Offsets.Bottom represent the distance in pixel from the Anchors Maximum.Y, effectively controlling the desired widget size. When the anchors are not well defined, the Offsets.Left and Offsets.Top represent the widget position and Offsets.Right and Offset.Bottom represent the widget size.
            Offsets<native><public>:margin = external {}

            # When true we use the widget's desired size. The size calculated by the Offsets is ignored.
            SizeToContent<native><public>:logic = external {}

            # Alignment is the pivot/origin point of the widget.
            # Starting in the upper left at (0.0,0.0), ending in the lower right at (1.0,1.0).
            Alignment<native><public>:vector2 = external {}

            # Z Order of this slot relative to other slots in this canvas panel.
            # Higher values are rendered last (and so they will appear to be on top)
            ZOrder<native><public>:type {_X:int where 0 <= _X, _X <= 2147483647} = external {}

            # The widget assigned to this slot.
            Widget<native><public>:widget

        # Make a canvas slot for fixed position widget.
        # If Size is set, then the Offsets is calculated and the SizeToContent is set to false.
        # If Size is not set, then Right and Bottom are set to zero and are not used. The widget size will be automatically calculated. The SizeToContent is set to true.
        # The widget is not anchored and will not move if the parent is resized.
        # The Anchors is set to zero.
        MakeCanvasSlot<native><public>(Widget:widget, Position:vector2, ?Size:vector2 = external {}, ?ZOrder:type {_X:int where 0 <= _X, _X <= 2147483647} = external {}, ?Alignment:vector2 = external {})<computes>:canvas_slot

        # A solid color widget.
        color_block<native><public> := class<final>(widget):
            # The color of the widget. Used only during initialization of the widget and not modified by SetColor.
            DefaultColor<native><public>:color = external {}

            # The opacity of the widget. Used only during initialization of the widget and not modified by SetOpacity.
            DefaultOpacity<native><public>:type {_X:float where 0.000000 <= _X, _X <= 1.000000} = external {}

            # The size this widget desired to be displayed in. Used only during initialization of the widget and not modified by SetDesiredSize.
            DefaultDesiredSize<native><public>:vector2 = external {}

            # Sets the widget's color.
            SetColor<native><public>(InColor:color):void

            # Gets the widget's color.
            GetColor<native><public>():color

            # Sets the widgets's opacity.
            SetOpacity<native><public>(InOpacity:type {_X:float where 0.000000 <= _X, _X <= 1.000000}):void

            # Gets the widget's opacity.
            GetOpacity<native><public>():type {_X:float where 0.000000 <= _X, _X <= 1.000000}

            # Sets the size this widget desired to be displayed in.
            SetDesiredSize<native><public>(InDesiredSize:vector2):void

            # Gets the size this widget desired to be displayed in.
            GetDesiredSize<native><public>():vector2

        # Tiling options values
        image_tiling<native><public> := enum:
            # Stretch the image to fit the available space.
            Stretch
            # Repeat/Wrap the image to fill the available space.
            Repeat

        # A widget to display a texture.
        texture_block<native><public> := class(widget):
            # The image to render. Used only during initialization of the widget and not modified by SetImage.
            DefaultImage<native><public>:texture

            # Tinting applied to the image. Used only during initialization of the widget and not modified by SetTint.
            DefaultTint<native><public>:color = external {}

            # The size this widget desired to be displayed in. Used only during initialization of the widget and not modified by SetDesiredSize.
            DefaultDesiredSize<native><public>:vector2 = external {}

            # The horizontal tiling option. Used only during initialization of the widget and not modified by SetTiling.
            DefaultHorizontalTiling<native><public>:image_tiling = external {}

            # The vertical tiling option. Used only during initialization of the widget and not modified by SetTiling.
            DefaultVerticalTiling<native><public>:image_tiling = external {}

            # Sets the image to render.
            SetImage<native><public>(InImage:texture):void

            # Gets the image to render.
            GetImage<native><public>():texture

            # Sets the tint applied to the image.
            SetTint<native><public>(InColor:color):void

            # Gets the tint applied to the image.
            GetTint<native><public>():color

            # Sets the size this widget desired to be displayed in.
            SetDesiredSize<native><public>(InDesiredSize:vector2):void

            # Gets the size this widget desired to be displayed in.
            GetDesiredSize<native><public>():vector2

            # Sets the tiling option when the image is smaller than the allocated size.
            SetTiling<native><public>(InHorizontalTiling:image_tiling, InVerticalTiling:image_tiling):void

            # Gets the tiling option.
            GetTiling<native><public>():tuple(image_tiling, image_tiling)

        # Overlay is a container consisting of widgets stacked on top of each other.
        overlay<native><public> := class<final>(widget):
            # The child widgets of the overlay. Used only during initialization of the widget and not modified by Add/RemoveWidget.
            Slots<native><public>:[]overlay_slot = external {}

            # Add a new child slot to the overlay. Slots are added at the end.
            AddWidget<native><public>(Slot:overlay_slot):void

            # Removes a slot containing the given widget
            RemoveWidget<native><public>(Widget:widget):void

        # Slot for an overlay widget
        overlay_slot<native><public> := struct:
            # The widget assigned to this slot.
            Widget<native><public>:widget

            # Horizontal alignment of the widget inside the slot.
            # This alignment is only applied after the layout space for the widget slot is created and determines the widget alignment within that space.
            HorizontalAlignment<native><public>:horizontal_alignment = external {}

            # Vertical alignment of the widget inside the slot.
            # This alignment is only applied after the layout space for the widget slot is created and determines the widget alignment within that space.
            VerticalAlignment<native><public>:vertical_alignment = external {}

            # Empty distance in pixels that surrounds the widget inside the slot. Assumes 1080p resolution.
            Padding<native><public>:margin = external {}

        # Stack box is a container of a list of widgets stacked either vertically or horizontally.
        stack_box<native><public> := class<final>(widget):
            # The child widgets of the stack box. Used only during initialization of the widget and not modified by Add/RemoveWidget.
            Slots<native><public>:[]stack_box_slot = external {}

            # The orientation of the stack box. Either stack widgets horizontal or vertical.
            Orientation<native><public>:orientation

            # Add a new child slot to the stack box. Slots are added at the end.
            AddWidget<native><public>(Slot:stack_box_slot):void

            # Removes a slot containing the given widget
            RemoveWidget<native><public>(Widget:widget):void

        # Slot for a stack_box widget
        stack_box_slot<native><public> := struct:
            # The widget assigned to this slot.
            Widget<native><public>:widget

            # Horizontal alignment of the widget inside the slot.
            # This alignment is only applied after the layout space for the widget slot is created and determines the widget alignment within that space.
            HorizontalAlignment<native><public>:horizontal_alignment = external {}

            # Vertical alignment of the widget inside the slot.
            # This alignment is only applied after the layout space for the widget slot is created and determines the widget alignment within that space.
            VerticalAlignment<native><public>:vertical_alignment = external {}

            # Empty distance in pixels that surrounds the widget inside the slot. Assumes 1080p resolution.
            Padding<native><public>:margin = external {}

            # The available space will be distributed proportionally.
            # If not set, the slot will use the desired size of the widget.
            Distribution<native><public>:?float = external {}

        # Text justification values:
        #   Left: Justify the text logically to the left based on current culture.
        #   Center: Justify the text in the center.
        #   Right: Justify the text logically to the right based on current culture.
        # The Left and Right value will flip when the local culture is right-to-left.
        text_justification<native><public> := enum:
            Left
            Center
            Right
            InvariantLeft
            InvariantRight

        # Text overflow policy values:
        #   Clip: Overflowing text will be clipped.
        #   Ellipsis: Overflowing text will be replaced with an ellipsis.
        text_overflow_policy<native><public> := enum:
            Clip
            Ellipsis

        # Base widget for text widget.
        text_base<native><public> := class<abstract>(widget):
            # The text to display to the user. Used only during initialization of the widget and not modified by SetText.
            DefaultText<native><localizes><public>:message = external {}

            # The color of the displayed text. Used only during initialization of the widget and not modified by SetTextColor.
            DefaultTextColor<native><public>:color = external {}

            # The opacity of the displayed text. Used only during initialization of the widget and not modified by SetTextOpacity.
            DefaultTextOpacity<native><public>:type {_X:float where 0.000000 <= _X, _X <= 1.000000} = external {}

            # The justification to display to the user. Used only during initialization of the widget and not modified by SetJustification.
            DefaultJustification<native><public>:text_justification = external {}

            # The policy that determine what happens when the text is longer than its allowed length.
            # Used only during initialization of the widget and not modified by SetOverflowPolicy.
            DefaultOverflowPolicy<native><public>:text_overflow_policy = external {}

            # Sets the text displayed in the widget.
            SetText<native><public>(InText:message):void

            # Gets the text currently in the widget.
            GetText<native><public>():[]char

            # Sets the text justification in the widget.
            SetJustification<native><public>(InJustification:text_justification):void

            # Gets the text justification in the widget.
            GetJustification<native><public>():text_justification

            # Sets the policy that determine what happens when the text is longer than its allowed length.
            SetOverflowPolicy<native><public>(InOverflowPolicy:text_overflow_policy):void

            # Gets the policy that determine what happens when the text is longer than its allowed length.
            GetOverflowPolicy<native><public>():text_overflow_policy

            # Sets the color of the displayed text.
            SetTextColor<native><public>(InColor:color):void

            # Gets the color of the displayed text.
            GetTextColor<native><public>():color

            # Sets the opacity of the displayed text.
            SetTextOpacity<native><public>(InOpacity:type {_X:float where 0.000000 <= _X, _X <= 1.000000}):void

            # Gets the opacity of the displayed text.
            GetTextOpacity<native><public>():type {_X:float where 0.000000 <= _X, _X <= 1.000000}
```