Struct Fold 

pub struct Fold;

Reduce (aka fold) function that reduces the provided tuple to a single value.

Type

(using arithmetic-typing notation)

(['T], 'Acc, ('Acc, 'T) -> 'Acc) -> 'Acc

Examples

let program = "
    xs = (1, -2, 3, -7);
    fold(xs, 1, |acc, x| acc * x) == 42
";
let program = Untyped::<F32Grammar>::parse_statements(program)?;
let module = ExecutableModule::new("test_fold", &program)?;

let mut env = Environment::new();
env.insert_native_fn("fold", fns::Fold);
assert_eq!(module.with_env(&env)?.run()?, Value::Bool(true));

Trait Implementations

impl Clone for Fold

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Fold

impl Debug for Fold

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

Formats the value using the given formatter.

impl Default for Fold

fn default() -> Self

Returns the “default value” for a type.

impl<T: 'static + Clone> NativeFn<T> for Fold

fn evaluate( &self, args: Vec<SpannedValue<T>>, ctx: &mut CallContext<'_, T>, ) -> EvalResult<T>

Executes the function on the specified arguments.