Struct Function 

pub struct Function<A: IVm>(/* private fields */);

A function value: it can be called, it has a length, it has a text, and it has an identity. Nothing else. It holds a VM’s own value, laid out as Unpacked lays out every value, which the VM constructs through its own capability, such as IStaticFunction, and Function::new wraps.

Compared by identity, an Rc in naive: every construction is a new function, as JavaScript makes a new function of every evaluation of an arrow, and (() => 1) === (() => 1) is false. A built-in is no kind apart: it is a closure of the runtime value, vm::runtime, built once and read from the value, so Object.is === Object.is holds because both reads find the one closure, and its text is the NativeFunction text the compiled runtime gave it (fjs/js/runtime/README.md, “How NaNVM finds it”).

Implementations

impl<A: IVm> Function<A>

pub fn new(internal: A::InternalFunction) -> Self

pub fn call(&self, args: Array<A>) -> Result<Any<A>, Any<A>>

Call the function with an arguments array. No user function reads this, so there is no receiver to pass.

pub fn length(&self) -> u32

f.length.

pub fn text(&self) -> Result<String<A>, Any<A>>

String(f): the text the function was given, or the refusal of a function without one (error::function_text).

Trait Implementations

impl<A: Clone + IVm> Clone for Function<A>

where A::InternalFunction: Clone,

fn clone(&self) -> Function<A>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<A: IVm> Debug for Function<A>

A fixed marker: Debug is a Rust diagnostic, not a program value, so it carries no text a program could observe.

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

Formats the value using the given formatter.

impl<A: IVm> From<Function<A>> for Unpacked<A>

fn from(value: Function<A>) -> Self

Converts to this type from the input type.

impl<A: IVm> PartialEq for Function<A>

Identity: a function is its own value, by reference.

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<A: IVm> TryFrom<Any<A>> for Function<A>

type Error = Any<A>

The type returned in the event of a conversion error.

fn try_from(value: Any<A>) -> Result<Self, Self::Error>

Performs the conversion.