Module reflect 

Available on crate feature reflect only.

The component registry: which components a bridge can address.

A component is any 'static type, so a world alone cannot name one. A component becomes addressable by submitting a ComponentEntry to a link-time table; the entry is the only place its name and its codec are written down.

The codec speaks [Partial] values rather than text: a caller that has a component in reflection form writes it without ever spelling it out, and one that has it as text fills a partial first. JSON is one such spelling, and encode_json, set_json and push_json are that front door; a bridge of another format uses the partials underneath it.

For a component that derives [facet::Facet] the entry carries no field list at all: its own struct fields are the JSON shape, and ComponentEntry::new turns that reflection into the codec. A component whose fields cannot be reflected – a GPU handle, a private field – reflects through a proxy instead, and one that cannot be written makes its proxy’s conversion fail, so a write reports why rather than inventing a value.

Entries are collected from wherever they are written, so a crate that defines its own components registers them itself – nothing has to be handed a registry. The table is link-time, so a crate whose entries are never reachable from the binary is not linked in either; a binary that wants a crate’s entries has to name that crate.

Re-exports

use facet::Characteristic; 🔒

use facet::Facet; 🔒

use facet::Facet; 🔒

use facet::Partial; 🔒

use facet::AllocError; 🔒

use facet::ReflectError; 🔒

use facet::ShapeMismatchError; 🔒

use facet_format::DeserializeError; 🔒

use facet_format::SerializeError; 🔒

use facet_json::JsonSerializeError; 🔒

use crate::DynamicBundle; 🔒

use crate::Entity; 🔒

use crate::EntityAccessError; 🔒

use crate::Scope; 🔒

Structs

ComponentEntry

One component a bridge can address.

Enums

ComponentError

Why the registry could not address a component.

Functions

contains

Whether a component with this name is submitted.

current_partial

A partial value over the entity’s current component, ready to be filled and handed back to set.

current_partial_component 🔒

A partial over the entity’s current C, seeded with a copy of it.

default_partial

A partial value over the named component’s Default, ready to be filled and handed to push.

default_partial_component 🔒

A partial over a fresh C, seeded with C’s Default when it has one.

describe 🔒

The backend’s own message, which [SerializeError]’s Display leaves out of the Backend variant.

encode_json

Entity’s name component as JSON text, or why either is missing.

encode_json_component 🔒

entries

Every submitted entry.

entry

The entry a name addresses, or ComponentError::Unknown naming the ones that exist.

fill 🔒

The partial a JSON patch produces over partial.

find 🔒

materialize 🔒

missing 🔒

Says which component was asked for and why the lookup failed: the handle may be dead or out of the scope’s reach, and each has its own reply.

names

The bare names of every submitted component.

push

Push the name component, taken from partial, into builder.

push_component 🔒

push_json

Push a name component decoded from JSON text into builder.

set

Overwrite entity’s name component with the value partial holds.

set_component 🔒

set_json

Overwrite entity’s name component from JSON text.

to_json 🔒

A value as JSON text, through the reflection it derives.