Macro frame_support::impl_runtime_metadata

macro_rules! impl_runtime_metadata {
    (
		for $runtime:ident with modules where Extrinsic = $ext:ident
			$( $rest:tt )*
	) => { ... };
}

Implements the metadata support for the given runtime and all its modules.

Example:

struct Runtime;
frame_support::impl_runtime_metadata! {
    for Runtime with modules where Extrinsic = UncheckedExtrinsic
        module0::Module as Module0 { index 0 } with,
        module1::Module as Module1 { index 1 } with,
        module2::Module as Module2 { index 2 } with Storage,
};

In this example, just MODULE3 implements the Storage trait.