MixinScript¶

Inherits: Script < Resource < Reference < Object

Experimental! A script which combines several other Script resources to extend object’s run-time functionality.

Description¶

MixinScript is a Script which allows to simulate a new class by fusing other Script resources into one. MixinScript is a cross-language implementation of the Mixin programming concept.

All objects that use MixinScript can have properties, methods and signals to be available in the same instance.

Mixin scripts are added either via editor or code using add_mixin. All mixin scripts added to MixinScript must inherit from Mixin class. MixinScript use internal Mixin instances to extend the behavior of the owner. You can treat Mixin objects as if they were the owners themselves, since all properties, methods and signals are going to be available in the owner at run-time, and are allowed to override virtual methods such as Node._ready, even if they don’t exist in the Mixin class. But do note that some languages like GDScript won’t be able to provide features like autocompletion, because in most cases, Mixin class may not represent the owner’s real base class.

If scripts share the same properties, methods or signals, only the first occurrence of those will be used throughout scripts. This means that name conflict resolution is implicit, so you may want to change the order of mixin scripts via editor or using move_mixin method at run-time.

Depending on the language, properties, methods and signals may not be directly available in the Mixin classes, but an instance of the class. Due to the nature of cross-language implementation, those languages might not be aware of the mixin mechanism used by MixinScript, leading to parse errors as seen in GDScript.

Properties¶

Array mixins [ ]

Methods¶

void	add_mixin ( Script script )
void	clear_mixins ( )
Script	get_mixin ( int index ) const
int	get_mixin_count ( ) const
void	insert_mixin ( int position, Script script )
void	move_mixin ( int position, Script script )
void	remove_mixin ( int index )
void	set_mixin ( int index, Script script )

Property Descriptions¶

Array mixins

Default	`[ ]`
Setter	set_mixins(value)
Getter	get_mixins()

An array of all Script mixins used by this script.

Method Descriptions¶

void add_mixin ( Script script )

Adds a new script to extend the behavior of the owner.

void clear_mixins ( )

Removes all mixins from this script.

Script get_mixin ( int index ) const

Returns a script at index previously added with add_mixin.

int get_mixin_count ( ) const

Returns the total number of scripts in MixinScript.

void insert_mixin ( int position, Script script )

Inserts a new script at a given position in the array of mixins. The behavior is equivalent to Array.insert.

void move_mixin ( int position, Script script )

Moves an existing script to a different position (order) among the other scripts. Since calls, signals, etc are performed in script order, changing the order of scripts may be necessary.

void remove_mixin ( int index )

Removes an existing script at index. The functionality of the old script will no longer be available in the instance that uses MixinScript.

void set_mixin ( int index, Script script )

Changes the script at index. The functionality of the old script will no longer be available in the instance that uses MixinScript.