Struct PatchFlag

pub struct PatchFlag { /* private fields */ }

Patch flags are optimization hints generated by the compiler. when a block with dynamicChildren is encountered during diff, the algorithm enters “optimized mode”. In this mode, we know that the vdom is produced by a render function generated by the compiler, so the algorithm only needs to handle updates explicitly marked by these patch flags.

Check the patchElement function in ‘../../runtime-core/src/renderer.ts’ to see how the flags are handled during diff.

Implementations

impl PatchFlag

pub const TEXT: Self

Indicates an element with dynamic textContent (children fast path)

pub const CLASS: Self

Indicates an element with dynamic class binding.

pub const STYLE: Self

Indicates an element with dynamic style The compiler pre-compiles static string styles into static objects and detects and hoists inline static objects e.g. style=“color: red” and :style=“{ color: ‘red’ }” both get hoisted as const style = { color: ‘red’ } render() { return e(‘div’, { style }) }

pub const PROPS: Self

Indicates an element that has non-class/style dynamic props. Can also be on a component that has any dynamic props (includes class/style). when this flag is present, the vnode also has a dynamicProps array that contains the keys of the props that may change so the runtime can diff them faster (without having to worry about removed props)

pub const FULL_PROPS: Self

Indicates an element with props with dynamic keys. When keys change, a full diff is always needed to remove the old key. This flag is mutually exclusive with CLASS, STYLE and PROPS.

pub const HYDRATE_EVENTS: Self

Indicates an element with event listeners (which need to be attached during hydration)

pub const STABLE_FRAGMENT: Self

Indicates a fragment whose children order doesn’t change.

pub const KEYED_FRAGMENT: Self

Indicates a fragment with keyed or partially keyed children

pub const UNKEYED_FRAGMENT: Self

Indicates a fragment with unkeyed children.

pub const NEED_PATCH: Self

Indicates an element that only needs non-props patching, e.g. ref or directives (onVnodeXXX hooks). since every patched vnode checks for refs and onVnodeXXX hooks, it simply marks the vnode so that a parent block will track it.

pub const DYNAMIC_SLOTS: Self

Indicates a component with dynamic slots (e.g. slot that references a v-for iterated value, or dynamic slot names). Components with this flag are always force updated.

pub const DEV_ROOT_FRAGMENT: Self

Indicates a fragment that was created only because the user has placed comments at the root level of a template. This is a dev-only flag since comments are stripped in production.

pub const HOISTED: Self

SPECIAL FLAGS ———————————————————–– Special flags are negative integers. They are never matched against using bitwise operators (bitwise matching should only happen in branches where patchFlag > 0), and are mutually exclusive. When checking for a special flag, simply check patchFlag === FLAG. Indicates a hoisted static vnode. This is a hint for hydration to skip the entire sub tree since static content never needs to be updated.

pub const BAIL: Self

A special flag that indicates that the diffing algorithm should bail out of optimized mode. For example, on block fragments created by renderSlot() when encountering non-compiler generated slots (i.e. manually written render functions, which should always be fully diffed) OR manually cloneVNodes

pub const fn empty() -> Self

Returns an empty set of flags.

pub const fn all() -> Self

Returns the set containing all flags.

pub const fn bits(&self) -> i32

Returns the raw value of the flags currently stored.

pub const fn from_bits(bits: i32) -> Option<Self>

Convert from underlying bit representation, unless that representation contains bits that do not correspond to a flag.

pub const fn from_bits_truncate(bits: i32) -> Self

Convert from underlying bit representation, dropping any bits that do not correspond to flags.

pub const unsafe fn from_bits_unchecked(bits: i32) -> Self

Convert from underlying bit representation, preserving all bits (even those not corresponding to a defined flag).

Safety

The caller of the bitflags! macro can chose to allow or disallow extra bits for their bitflags type.

The caller of from_bits_unchecked() has to ensure that all bits correspond to a defined flag or that extra bits are valid for this bitflags type.

pub const fn is_empty(&self) -> bool

Returns true if no flags are currently stored.

pub const fn is_all(&self) -> bool

Returns true if all flags are currently set.

pub const fn intersects(&self, other: Self) -> bool

Returns true if there are flags common to both self and other.

pub const fn contains(&self, other: Self) -> bool

Returns true if all of the flags in other are contained within self.

pub fn insert(&mut self, other: Self)

Inserts the specified flags in-place.

pub fn remove(&mut self, other: Self)

Removes the specified flags in-place.

pub fn toggle(&mut self, other: Self)

Toggles the specified flags in-place.

pub fn set(&mut self, other: Self, value: bool)

Inserts or removes the specified flags depending on the passed value.

pub const fn intersection(self, other: Self) -> Self

Returns the intersection between the flags in self and other.

Specifically, the returned set contains only the flags which are present in both self and other.

This is equivalent to using the & operator (e.g. ops::BitAnd), as in flags & other.

pub const fn union(self, other: Self) -> Self

Returns the union of between the flags in self and other.

Specifically, the returned set contains all flags which are present in either self or other, including any which are present in both (see Self::symmetric_difference if that is undesirable).

This is equivalent to using the | operator (e.g. ops::BitOr), as in flags | other.

pub const fn difference(self, other: Self) -> Self

Returns the difference between the flags in self and other.

Specifically, the returned set contains all flags present in self, except for the ones present in other.

It is also conceptually equivalent to the “bit-clear” operation: flags & !other (and this syntax is also supported).

This is equivalent to using the - operator (e.g. ops::Sub), as in flags - other.

pub const fn symmetric_difference(self, other: Self) -> Self

Returns the symmetric difference between the flags in self and other.

Specifically, the returned set contains the flags present which are present in self or other, but that are not present in both. Equivalently, it contains the flags present in exactly one of the sets self and other.

This is equivalent to using the ^ operator (e.g. ops::BitXor), as in flags ^ other.

pub const fn complement(self) -> Self

Returns the complement of this set of flags.

Specifically, the returned set contains all the flags which are not set in self, but which are allowed for this type.

Alternatively, it can be thought of as the set difference between Self::all() and self (e.g. Self::all() - self)

This is equivalent to using the ! operator (e.g. ops::Not), as in !flags.

Trait Implementations

impl Binary for PatchFlag

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

Formats the value using the given formatter.

impl BitAnd for PatchFlag

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

Returns the intersection between the two sets of flags.

type Output = PatchFlag

The resulting type after applying the & operator.

impl BitAndAssign for PatchFlag

fn bitand_assign(&mut self, other: Self)

Disables all flags disabled in the set.

impl BitOr for PatchFlag

fn bitor(self, other: PatchFlag) -> Self

Returns the union of the two sets of flags.

type Output = PatchFlag

The resulting type after applying the | operator.

impl BitOrAssign for PatchFlag

fn bitor_assign(&mut self, other: Self)

Adds the set of flags.

impl BitXor for PatchFlag

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

Returns the left flags, but with all the right flags toggled.

type Output = PatchFlag

The resulting type after applying the ^ operator.

impl BitXorAssign for PatchFlag

fn bitxor_assign(&mut self, other: Self)

Toggles the set of flags.

impl Clone for PatchFlag

fn clone(&self) -> PatchFlag

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PatchFlag

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

Formats the value using the given formatter.

impl Default for PatchFlag

fn default() -> PatchFlag

Returns the “default value” for a type.

impl Extend<PatchFlag> for PatchFlag

fn extend<T: IntoIterator<Item = Self>>(&mut self, iterator: T)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl FromIterator<PatchFlag> for PatchFlag

fn from_iter<T: IntoIterator<Item = Self>>(iterator: T) -> Self

Creates a value from an iterator.

impl Hash for PatchFlag

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, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl LowerHex for PatchFlag

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

Formats the value using the given formatter.

impl Not for PatchFlag

fn not(self) -> Self

Returns the complement of this set of flags.

type Output = PatchFlag

The resulting type after applying the ! operator.

impl Octal for PatchFlag

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

Formats the value using the given formatter.

impl Ord for PatchFlag

fn cmp(&self, other: &PatchFlag) -> Ordering

This method returns an Ordering between self and other.

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

where Self: Sized,

Compares and returns the maximum of two values.

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

where Self: Sized,

Compares and returns the minimum of two values.

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

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for PatchFlag

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

Tests for self and other values to be equal, and is used by ==.

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 PartialOrd for PatchFlag

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

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

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

Tests less than (for self and other) and is used by the < operator.

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

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

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

Tests greater than (for self and other) and is used by the > operator.

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

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

impl Serialize for PatchFlag

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Sub for PatchFlag

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

Returns the set difference of the two sets of flags.

type Output = PatchFlag

The resulting type after applying the - operator.

impl SubAssign for PatchFlag

fn sub_assign(&mut self, other: Self)

Disables all flags enabled in the set.

impl UpperHex for PatchFlag

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

Formats the value using the given formatter.

impl Copy for PatchFlag

impl Eq for PatchFlag

impl StructuralPartialEq for PatchFlag