Struct tvix_eval::value::thunk::Thunk

pub struct Thunk(Rc<RefCell<ThunkRepr>>);

A thunk is created for any value which requires non-strict evaluation due to self-reference or lazy semantics (or both). Every reference cycle involving Values will contain at least one Thunk.

Tuple Fields

0: Rc<RefCell<ThunkRepr>>

Implementations

impl Thunk

pub fn new_closure(lambda: Rc<Lambda>) -> Self

pub fn new_suspended(lambda: Rc<Lambda>, span: Span) -> Self

pub fn new_suspended_native( native: Box<dyn Fn() -> Result<Value, ErrorKind>>, ) -> Self

pub fn new_suspended_call(callee: Value, arg: Value, span: Span) -> Self

Helper function to create a Thunk that calls a function given as the Value callee with the argument arg when it is forced. This is particularly useful in builtin implementations if the result of calling a function does not need to be forced immediately, because e.g. it is stored in an attribute set.

fn prepare_blackhole(&self, forced_at: Span) -> ThunkRepr

pub async fn force( myself: Thunk, co: GenCo, span: Span, ) -> Result<Value, ErrorKind>

pub async fn force_( myself: Thunk, co: &GenCo, span: Span, ) -> Result<Value, ErrorKind>

pub fn finalise(&self, stack: &[Value])

pub fn is_evaluated(&self) -> bool

pub fn is_suspended(&self) -> bool

pub fn is_forced(&self) -> bool

Returns true if forcing this thunk will not change it.

pub fn value(&self) -> Ref<'_, Value>

Returns a reference to the inner evaluated value of a thunk. It is an error to call this on a thunk that has not been forced, or is not otherwise known to be fully evaluated.

fn unwrap_or_clone(self) -> Value

Returns the inner evaluated value of a thunk, cloning it if the Rc has more than one strong reference. It is an error to call this on a thunk that has not been forced, or is not otherwise known to be fully evaluated.

pub fn upvalues(&self) -> Ref<'_, Upvalues>

pub fn upvalues_mut(&self) -> RefMut<'_, Upvalues>

pub(crate) fn ptr_eq(&self, other: &Self) -> bool

Do not use this without first reading and understanding tvix/docs/value-pointer-equality.md.

pub(crate) fn debug_repr(&self) -> String

Helper function to format thunks in observer output.

Trait Implementations

impl Clone for Thunk

fn clone(&self) -> Thunk

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Thunk

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

Formats the value using the given formatter.

impl TotalDisplay for Thunk

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