Differences from other DI frameworks¶

@Binds and @Provides declarations can be added directly within graphs and their supertypes.
- @BindingContainer is the Metro equivalent of a Dagger @Module but it should rarely be used.
- @BindingContainer cannot declare graph extensions in the way @Module can declare subcomponents. Use @ContributesGraphExtension.
There is no Producers support.
There is no Hilt support, though some features are similar in the same way that Anvil’s features are similar.
There is no @Reusable.
There is no @BindsOptionalOf. Instead, Metro supports default optional dependencies.
There is no @Subcomponent. Instead, Metro uses graph extensions.
Metro can inject private properties and functions.
There is no @BindsInstance. Use @Provides on @DependencyGraph.Factory function parameters instead
Component dependencies must be annotated with @Includes.
Metro does not process Java code.
@Multibinds declarations are implemented in Metro graphs to return the declared multibinding.
Empty multibindings are an error by default in Metro. To allow a multibinding to be empty, it must be declared with @Multibinds(allowEmpty = true).
Metro graph classes may not directly extend other graph classes. You should use @Extends instead in Metro.
Dagger technically allows this, but only accessors and injectors cross these boundaries.

typealiases are not treated as implicit qualifiers.
Dependency graph classes cannot have primary constructors, their parameters must be defined as @Provides or graph parameters on a @DependencyGraph.Factory function like Dagger.
Higher order functions cannot be used. Instead, use Provider and declared @AssistedFactory-annotated types.
No need for use-site targets for most annotations.
No need for @get:Provides Impl.bind: Type get() = this to achieve type bindings. See the docs on @Binds.
Metro can inject private properties and functions.
When extending parent graphs, they must be annotated with @Extends in the child graph’s creator.
Metro does not process Java code.
Metro does not support assisted parameters in @Provides functions.

There is no rank in Metro’s @Contributes* annotations.
- Note that if Anvil interop is enabled, its rank properties are supported in interop.
@ContributesBinding uses a binding API to support generic bound types. See the aggregation docs for more info.
- Note that if Anvil interop is enabled, its boundType properties are supported in interop.
@Contributes*.replaces cannot replace classes in the same compilation as the graph that is merging them
Metro only merges graphs and cannot merge arbitrary interfaces.

There is no need for @CreateComponent or expect fun createComponent() functions.
@ContributesBinding uses a binding API to support generic bound types. See the aggregation docs for more info.
- Note that if Anvil interop is enabled, its boundType properties are supported in interop.
@Contributes*.replaces cannot replace classes in the same compilation as the graph that is merging them