Struct Function 

pub struct Function { /* private fields */ }

The type that represents functions themselves (eg PROMPT, +, =, etc.) within Knight.

Note that Functions cannot be created directly—you must fetch them. New functions can be registered if so desired.

Implementations

impl Function

pub fn func( &self, ) -> fn(&[Value], &mut Environment<'_, '_, '_>) -> Result<Value>

Gets the function pointer associated with self.

pub fn run( &self, args: &[Value], env: &mut Environment<'_, '_, '_>, ) -> Result<Value>

Executes this function with the given arguments

pub fn arity(&self) -> usize

Gets the arity of this function.

pub fn name(&self) -> char

Gets the name of the function.

pub fn fetch(name: char) -> Option<Self>

Gets the function associate dwith the given name, returning None if no such function exists.

pub fn register( name: char, arity: usize, func: fn(&[Value], &mut Environment<'_, '_, '_>) -> Result<Value>, )

Registers a new function with the given name, discarding any previous value associated with it.

Trait Implementations

impl Clone for Function

fn clone(&self) -> Function

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Function

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

Formats the value using the given formatter.

impl Hash for Function

fn hash<H: Hasher>(&self, h: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Function

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

Checks to see if two functions are identical.

Two functions are considered the same if their names, arities, and function pointers are identical.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Function

impl Eq for Function