Module template

Expand description

Functionality that relates to the Template trait.

Structs§

FnTemplate: A Template driven by a function that returns an output. This is used to create “free floating” templates without defining a new type. See template for usage.
InnerSceneEntityReference: The inner struct actually storing the unique index
SceneEntityReference: A unique reference for a named entity in a scene. Usually used by bevy_scene in generated code
SceneEntityReferences: Struct to store a mapping from SceneEntityReference to Entity which are used for resolving #Name entity references in bsn! macros
TemplateContext: The context used to apply the current Template. This contains a reference to the entity that the template is being applied to (via an EntityWorldMut).
TemplateTuple: A wrapper over a tuple of Template implementations, which also implements Template. This exists because Template cannot be directly implemented for tuples of Template implementations.
VecTemplate: A Template for Vec.

BuiltInTemplate: Roughly equivalent to FromTemplate, but does not have a blanket implementation for Default + Clone types. This is generally used for common generic collection types like Option and Vec, which have Default + Clone impls and therefore also pick up the FromTemplate behavior. This is fine when the T in Option<T> is not “templated” (ex: does not have an explicit FromTemplate derive). But if T is “templated”, such as Option<Handle<T>>, then it would require a manual #[template(OptionTemplate<HandleTemplate<T>>)] field annotation. This isn’t fun to type out.
FromTemplate: FromTemplate is implemented for types that can be produced by a specific, canonical Template. This creates a way to correlate to the Template using the desired template output type. This is used by Bevy’s scene system.
SpecializeFromTemplate: This is used to help improve error messages related to FromTemplate specialization. Developers should generally just ignore this trait and read the error message when they encounter it.
Template: A Template is something that, given a spawn context (target Entity, World, etc), can produce a Template::Output.

template: Returns a “free floating” template for a given func. This prevents the need to define a custom type for one-off templates.