Trait druid::piet::cairo::glib::bitflags::_core::iter::Extend

1.0.0 · source ·

pub trait Extend<A> {
    // Required method
    fn extend<T>(&mut self, iter: T)
       where T: IntoIterator<Item = A>;

    // Provided methods
    fn extend_one(&mut self, item: A) { ... }
    fn extend_reserve(&mut self, additional: usize) { ... }
}

Expand description

Extend a collection with the contents of an iterator.

Iterators produce a series of values, and collections can also be thought of as a series of values. The Extend trait bridges this gap, allowing you to extend a collection by including the contents of that iterator. When extending a collection with an already existing key, that entry is updated or, in the case of collections that permit multiple entries with equal keys, that entry is inserted.

Examples

Basic usage:

// You can extend a String with some chars:
let mut message = String::from("The first three letters are: ");

message.extend(&['a', 'b', 'c']);

assert_eq!("abc", &message[29..32]);

Implementing Extend:

// A sample collection, that's just a wrapper over Vec<T>
#[derive(Debug)]
struct MyCollection(Vec<i32>);

// Let's give it some methods so we can create one and add things
// to it.
impl MyCollection {
    fn new() -> MyCollection {
        MyCollection(Vec::new())
    }

    fn add(&mut self, elem: i32) {
        self.0.push(elem);
    }
}

// since MyCollection has a list of i32s, we implement Extend for i32
impl Extend<i32> for MyCollection {

    // This is a bit simpler with the concrete type signature: we can call
    // extend on anything which can be turned into an Iterator which gives
    // us i32s. Because we need i32s to put into MyCollection.
    fn extend<T: IntoIterator<Item=i32>>(&mut self, iter: T) {

        // The implementation is very straightforward: loop through the
        // iterator, and add() each element to ourselves.
        for elem in iter {
            self.add(elem);
        }
    }
}

let mut c = MyCollection::new();

c.add(5);
c.add(6);
c.add(7);

// let's extend our collection with three more numbers
c.extend(vec![1, 2, 3]);

// we've added these elements onto the end
assert_eq!("MyCollection([5, 6, 7, 1, 2, 3])", format!("{c:?}"));

Required Methods§

source

fn extend<T>(&mut self, iter: T)where T: IntoIterator<Item = A>,

Extends a collection with the contents of an iterator.

As this is the only required method for this trait, the trait-level docs contain more details.

Examples

Basic usage:

// You can extend a String with some chars:
let mut message = String::from("abc");

message.extend(['d', 'e', 'f'].iter());

assert_eq!("abcdef", &message);

Provided Methods§

source

fn extend_one(&mut self, item: A)

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

Extends a collection with exactly one element.

source

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.

The default implementation does nothing.

Trait druid::piet::cairo::glib::bitflags::_core::iter::Extend

Examples

Required Methods§

fn extend<T>(&mut self, iter: T)where T: IntoIterator<Item = A>,

Examples

Provided Methods§

fn extend_one(&mut self, item: A)

fn extend_reserve(&mut self, additional: usize)

Implementors§

impl Extend<PathEl> for druid::piet::kurbo::BezPath

impl Extend<char> for String

impl Extend<()> for ()

impl Extend<PdfOutline> for PdfOutline

impl Extend<BindingFlags> for BindingFlags

impl Extend<FormatSizeFlags> for FormatSizeFlags

impl Extend<IOCondition> for IOCondition

impl Extend<KeyFileFlags> for KeyFileFlags

impl Extend<LogLevelFlags> for LogLevelFlags

impl Extend<LogLevels> for LogLevels

impl Extend<OptionFlags> for OptionFlags

impl Extend<ParamFlags> for ParamFlags

impl Extend<SignalFlags> for SignalFlags

impl Extend<SpawnFlags> for SpawnFlags

impl Extend<Box<str, Global>> for String

impl Extend<String> for String

impl Extend<OsString> for OsString

impl Extend<AccelFlags> for AccelFlags

impl Extend<AnchorHints> for AnchorHints

impl Extend<AppInfoCreateFlags> for AppInfoCreateFlags

impl Extend<ApplicationFlags> for ApplicationFlags

impl Extend<ApplicationInhibitFlags> for ApplicationInhibitFlags

impl Extend<AskPasswordFlags> for AskPasswordFlags

impl Extend<AxisFlags> for AxisFlags

impl Extend<BusNameOwnerFlags> for BusNameOwnerFlags

impl Extend<BusNameWatcherFlags> for BusNameWatcherFlags

impl Extend<CalendarDisplayOptions> for CalendarDisplayOptions

impl Extend<CellRendererState> for CellRendererState

impl Extend<ConverterFlags> for ConverterFlags

impl Extend<DBusCallFlags> for DBusCallFlags

impl Extend<DBusCapabilityFlags> for DBusCapabilityFlags

impl Extend<DBusConnectionFlags> for DBusConnectionFlags

impl Extend<DBusInterfaceSkeletonFlags> for DBusInterfaceSkeletonFlags

impl Extend<DBusMessageFlags> for DBusMessageFlags

impl Extend<DBusProxyFlags> for DBusProxyFlags

impl Extend<DBusSendMessageFlags> for DBusSendMessageFlags

impl Extend<DBusServerFlags> for DBusServerFlags

impl Extend<DBusSignalFlags> for DBusSignalFlags

impl Extend<DestDefaults> for DestDefaults

impl Extend<DialogFlags> for DialogFlags

impl Extend<DragAction> for DragAction

impl Extend<DriveStartFlags> for DriveStartFlags

impl Extend<EventMask> for EventMask

impl Extend<FileAttributeInfoFlags> for FileAttributeInfoFlags

impl Extend<FileCopyFlags> for FileCopyFlags

impl Extend<FileCreateFlags> for FileCreateFlags

impl Extend<FileFilterFlags> for FileFilterFlags

impl Extend<FileMeasureFlags> for FileMeasureFlags

impl Extend<FileMonitorFlags> for FileMonitorFlags

impl Extend<FileQueryInfoFlags> for FileQueryInfoFlags

impl Extend<FontMask> for FontMask

impl Extend<FrameClockPhase> for FrameClockPhase

impl Extend<HyperlinkStateFlags> for HyperlinkStateFlags

impl Extend<IOStreamSpliceFlags> for IOStreamSpliceFlags

impl Extend<IconLookupFlags> for IconLookupFlags

impl Extend<InputHints> for InputHints

impl Extend<JunctionSides> for JunctionSides

impl Extend<ModifierType> for ModifierType

impl Extend<Modifiers> for Modifiers

impl Extend<MountMountFlags> for MountMountFlags

impl Extend<MountUnmountFlags> for MountUnmountFlags

impl Extend<OutputStreamSpliceFlags> for OutputStreamSpliceFlags

impl Extend<PathEl> for BezPath

impl Extend<PixbufFormatFlags> for PixbufFormatFlags

impl Extend<PlacesOpenFlags> for PlacesOpenFlags

impl Extend<RecentFilterFlags> for RecentFilterFlags

impl Extend<RegionFlags> for RegionFlags

impl Extend<ResourceLookupFlags> for ResourceLookupFlags

impl Extend<SeatCapabilities> for SeatCapabilities

impl Extend<SerializeFlags> for SerializeFlags

impl Extend<SettingsBindFlags> for SettingsBindFlags