Struct starlark::values::ValueOf

pub struct ValueOf<'v, T: UnpackValue<'v>> {
    pub value: Value<'v>,
    pub typed: T,
}

A wrapper that keeps the original value on the heap for use elsewhere, and also, when unpacked, unpacks the value to validate it is of the correct type. Has an UnpackValue instance, so often used as an argument to #[starlark_module] defined functions.

Two container specializations of this are ListOf and DictOf, which validate the types of their containers on unpack, but do not store the resulting Vec/Map

Fields

value: Value<'v>

The original Value on the same heap.

typed: T

The value that was unpacked.

Trait Implementations

impl<'v, T: UnpackValue<'v>> AllocValue<'v> for ValueOf<'v, T>

fn alloc_value(self, _heap: &'v Heap) -> Value<'v>

Allocate the value on a heap and return a reference to the allocated value.

impl<'v, T: Clone + UnpackValue<'v>> Clone for ValueOf<'v, T>

fn clone(&self) -> ValueOf<'v, T>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'v, T: Debug + UnpackValue<'v>> Debug for ValueOf<'v, T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'v, T: UnpackValue<'v>> Deref for ValueOf<'v, T>

type Target = Value<'v>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'v, T: UnpackValue<'v> + Dupe> Dupe for ValueOf<'v, T>

fn dupe(&self) -> Self

impl<'v, T: UnpackValue<'v>> StarlarkTypeRepr for ValueOf<'v, T>

fn starlark_type_repr() -> Ty

The representation of a type that a user would use verbatim in starlark type annotations

impl<'v, T: UnpackValue<'v>> UnpackValue<'v> for ValueOf<'v, T>

fn expected() -> String

Description of values acceptable by unpack_value, e. g. list or str.

fn unpack_value(value: Value<'v>) -> Option<Self>

Given a Value, try and unpack it into the given type, which may involve some element of conversion.

fn unpack_value_err(value: Value<'v>) -> Result<Self>

Unpack a value, but return error instead of None if unpacking fails.

fn unpack_param(value: Value<'v>) -> Result<Self>

Unpack value, but instead of None return error about incorrect argument type.

fn unpack_named_param(value: Value<'v>, param_name: &str) -> Result<Self>

Unpack value, but instead of None return error about incorrect named argument type.

impl<'v, T: Copy + UnpackValue<'v>> Copy for ValueOf<'v, T>