Struct ShapeBuilder 

pub struct ShapeBuilder { /* private fields */ }

Builder for creating Shape instances.

This builder provides a convenient way to construct Shape values with sensible defaults. Many fields can be inferred or have reasonable defaults:

ShapeBuilder::for_sized::<MyType>("MyType")
    .def(Def::Scalar)
    .vtable(my_vtable)
    .build()

Implementations

impl ShapeBuilder

pub const fn for_sized<T>(type_identifier: &'static str) -> Self

Create a new builder for a sized type.

The id and layout are derived from the type parameter.

pub const fn for_unsized<T: ?Sized>(type_identifier: &'static str) -> Self

Create a new builder for an unsized type.

pub const fn vtable(self, vtable: VTableErased) -> Self

Set the vtable (type-erased).

pub const fn vtable_direct(self, vtable: &'static VTableDirect) -> Self

Set the vtable from a direct vtable reference.

pub const fn vtable_indirect(self, vtable: &'static VTableIndirect) -> Self

Set the vtable from an indirect vtable reference.

pub const fn type_ops(self, type_ops: TypeOps) -> Self

Set the per-type operations (drop, default, clone) using the erased enum.

For generic containers, use this to provide the monomorphized operations while sharing the main vtable across all instantiations.

pub const fn type_ops_direct(self, type_ops: &'static TypeOpsDirect) -> Self

Set per-type operations for concrete types (uses thin pointers).

Use this for scalars, String, and derived structs/enums.

pub const fn type_ops_indirect(self, type_ops: &'static TypeOpsIndirect) -> Self

Set per-type operations for generic containers (uses wide pointers).

Use this for Vec<T>, Option<T>, Arc<T>, etc.

pub const fn add_marker_trait(self, trait_flag: MarkerTraits) -> Self

Add a marker trait flag.

pub const fn marker_traits(self, traits: MarkerTraits) -> Self

Set all marker traits at once using combined bitflags.

pub const fn eq(self) -> Self

Mark type as implementing Eq.

pub const fn copy(self) -> Self

Mark type as implementing Copy.

pub const fn send(self) -> Self

Mark type as implementing Send.

pub const fn sync(self) -> Self

Mark type as implementing Sync.

pub const fn unpin(self) -> Self

Mark type as implementing Unpin.

pub const fn unwind_safe(self) -> Self

Mark type as implementing UnwindSafe.

pub const fn ref_unwind_safe(self) -> Self

Mark type as implementing RefUnwindSafe.

pub const fn ty(self, ty: Type) -> Self

Set the type.

pub const fn def(self, def: Def) -> Self

Set the definition.

pub const fn type_params(self, type_params: &'static [TypeParam]) -> Self

Set the type parameters.

pub const fn doc(self, doc: &'static [&'static str]) -> Self

Set the documentation.

pub const fn attributes(self, attributes: &'static [Attr]) -> Self

Set the attributes.

pub const fn type_tag(self, type_tag: &'static str) -> Self

Set the type tag.

pub const fn inner(self, inner: &'static Shape) -> Self

Set the inner shape (for transparent/newtype wrappers).

pub const fn builder_shape(self, builder: &'static Shape) -> Self

Set the builder shape for immutable collections.

If set, deserializers will build the value using the builder shape, then convert to the target type. Used for immutable collections like Bytes (builds through BytesMut) or Arc<[T]> (builds through Vec<T>).

pub const fn type_name(self, type_name: TypeNameFn) -> Self

Set the type name function for formatting generic type names.

For generic types like Vec<T>, this function formats the full name including type parameters (e.g., Vec<String>).

pub const fn proxy(self, proxy: &'static ProxyDef) -> Self

Set the container-level proxy for custom serialization/deserialization.

When a proxy is set, the type will be serialized/deserialized through the proxy type instead of directly.

pub const fn variance(self, variance: fn(&'static Shape) -> Variance) -> Self

Set the variance function for this type.

For derived types, use Shape::computed_variance which walks fields. For leaf types, use Variance::COVARIANT, Variance::INVARIANT, etc.

pub const fn flags(self, flags: ShapeFlags) -> Self

Set the flags for this shape.

pub const fn untagged(self) -> Self

Mark this enum as untagged.

Untagged enums serialize their content directly without any discriminant.

pub const fn tag(self, tag: &'static str) -> Self

Set the tag field name for internally/adjacently tagged enums.

pub const fn content(self, content: &'static str) -> Self

Set the content field name for adjacently tagged enums.

pub const fn build(self) -> Shape

Build the Shape.

If ty was not explicitly set (still Type::Undefined), it will be inferred from def.