Enum DataState

pub enum DataState<T, E: ErrorBounds = Error> {
    None,
    AwaitingResponse(Awaiting<T, E>),
    Present(T),
    Failed(DataStateError<E>),
}

Used to store a type that is not always available and we need to keep polling it to get it ready

Variants

None

Represent no data present and not pending

AwaitingResponse(Awaiting<T, E>)

Represents data has been requested and awaiting it being available

Present(T)

Represents data that is available for use

Failed(DataStateError<E>)

Represents an error that Occurred

Implementations

impl<T, E: ErrorBounds> DataState<T, E>

pub fn egui_get<F>( &mut self, ui: &mut Ui, retry_msg: Option<&str>, fetch_fn: F, ) -> CanMakeProgress

where F: FnOnce() -> Awaiting<T, E>,

Attempts to load the data and displays appropriate UI if applicable. Some branches lead to no UI being displayed, in particular when the data or an error is received (On the expectation it will show next frame). When in an error state the error messages will show as applicable. If called an already has data present this function does nothing and returns [CanMakeProgress::UnableToMakeProgress]

If a retry_msg is provided then it overrides the default

Note see Self::get for more info.

pub fn get<F>(&mut self, fetch_fn: F) -> CanMakeProgress

where F: FnOnce() -> Awaiting<T, E>,

Attempts to load the data and returns if it is able to make progress.

Note: F needs to return AwaitingType<T> and not T because it needs to be able to be pending if T is not ready.

pub fn await_data(rx: &mut Awaiting<T, E>) -> Option<Self>

Checks to see if the data is ready and if it is returns a new Self otherwise None.

pub fn is_present(&self) -> bool

Returns true if the data state is Present.

pub fn is_none(&self) -> bool

Returns true if the data state is None.

Trait Implementations

impl<T, E: ErrorBounds> AsMut<DataState<T, E>> for DataState<T, E>

fn as_mut(&mut self) -> &mut DataState<T, E>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<T, E: ErrorBounds> AsRef<DataState<T, E>> for DataState<T, E>

fn as_ref(&self) -> &DataState<T, E>

Converts this type into a shared reference of the (usually inferred) input type.

impl<T: Debug, E: Debug + ErrorBounds> Debug for DataState<T, E>

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

Formats the value using the given formatter.

impl<T, E: ErrorBounds> Default for DataState<T, E>

fn default() -> DataState<T, E>

Returns the “default value” for a type.