Trait bevy_yarnspinner::prelude::VariableStorage

pub trait VariableStorage: Debug + Send + Sync {
    // Required methods
    fn clone_shallow(&self) -> Box<dyn VariableStorage>;
    fn set(
        &mut self,
        name: String,
        value: YarnValue
    ) -> Result<(), VariableStorageError>;
    fn get(&self, name: &str) -> Result<YarnValue, VariableStorageError>;
    fn extend(
        &mut self,
        values: HashMap<String, YarnValue>
    ) -> Result<(), VariableStorageError>;
    fn variables(&self) -> HashMap<String, YarnValue>;
    fn clear(&mut self);
    fn as_any(&self) -> &(dyn Any + 'static);
    fn as_any_mut(&mut self) -> &mut (dyn Any + 'static);

    // Provided method
    fn contains(&self, name: &str) -> bool { ... }
}

Expand description

Provides a mechanism for storing and retrieving instances of the YarnValue type.

§Implementation notes

The interface has been changed to make use of our YarnValue type, which is more domain specific than the semi-corresponding Convertible. We also cannot use generics in this trait because we need to be able to clone this box.

Required Methods§

fn clone_shallow(&self) -> Box<dyn VariableStorage>

Creates a shallow clone of this variable storage, i.e. a clone that shares the same underlying storage and will thus be perfectly in sync with the original instance.

fn set( &mut self, name: String, value: YarnValue ) -> Result<(), VariableStorageError>

Sets the value of a variable. Must fail with a [VariableStorageError::InvalidVariableName] if the variable name does not start with a $.

fn get(&self, name: &str) -> Result<YarnValue, VariableStorageError>

Gets the value of a variable. Must fail with a [VariableStorageError::InvalidVariableName] if the variable name does not start with a $. If the variable is not defined, must fail with a [VariableStorageError::VariableNotFound].

fn extend( &mut self, values: HashMap<String, YarnValue> ) -> Result<(), VariableStorageError>

Extends this variable storage with the given values. Must fail with a [VariableStorageError::InvalidVariableName] if any of the variable names do not start with a $. Existing variables must be overwritten.

fn variables(&self) -> HashMap<String, YarnValue>

Returns a map of all variables in this variable storage.

fn clear(&mut self)

Clears all variables in this variable storage.

fn as_any(&self) -> &(dyn Any + 'static)

Gets the VariableStorage as a trait object. This allows retrieving the concrete type by downcasting, using the downcast_ref method available through the Any trait.

fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)

Gets the VariableStorage as a mutable trait object. This allows retrieving the concrete type by downcasting, using the downcast_mut method available through the Any trait.