Struct fj_kernel::shape::Handle

pub struct Handle<T> { /* private fields */ }

A handle to an object stored within [Shape]

If an object of type T (this could be Curve, Vertex, etc.) is added to Shape, a Handle<T> is returned. This handle is then used in topological types to refer to the object, instead of having those types own an instance of the object.

This approach has two advantages:

1. The object can’t be mutated through the handle. Since an object can be referred to by multiple other objects, mutating it locally would have no effect on those other references. Handle preventing that removes this source of errors.
2. The object is guaranteed to be in Shape, as Handles can’t be created any other way. This means that if the Shape needs to be modified, any objects can be updated once, without requiring an update of all the other objects that reference it.

Equality

The equality of Handle is very strictly defined in terms of identity. Two Handles are considered equal, if they refer to objects in the same memory location.

Implementations

impl<T> Handle<T>

pub fn get(&self) -> T where
    T: Clone, 

Access the object that the handle references

Trait Implementations

impl<T: Clone> Clone for Handle<T>

fn clone(&self) -> Handle<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Handle<T>

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

Formats the value using the given formatter.

impl<T: Hash> Hash for Handle<T>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

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

Feeds a slice of this type into the given Hasher.

impl<T: Ord> Ord for Handle<T>

fn cmp(&self, other: &Handle<T>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl<T: PartialEq> PartialEq<Handle<T>> for Handle<T>

fn eq(&self, other: &Handle<T>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Handle<T>) -> bool

This method tests for !=.

impl<T: PartialOrd> PartialOrd<Handle<T>> for Handle<T>

fn partial_cmp(&self, other: &Handle<T>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

This method tests less than (for self and other) and is used by the < operator.

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

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

This method tests greater than (for self and other) and is used by the > operator.

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<T: Eq> Eq for Handle<T>

impl<T> StructuralEq for Handle<T>

impl<T> StructuralPartialEq for Handle<T>