Derive Macro rustc_macros::TypeFoldable
source · #[derive(TypeFoldable)]
{
// Attributes available to this derive:
#[type_foldable]
}
Expand description
Derives TypeFoldable
for the annotated struct
or enum
(union
is not supported).
The fold will produce a value of the same struct or enum variant as the input, with
each field respectively folded using the TypeFoldable
implementation for its type.
However, if a field of a struct or an enum variant is annotated with
#[type_foldable(identity)]
then that field will retain its incumbent value (and its
type is not required to implement TypeFoldable
).