Struct Var 

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

Data structure for storing a single value.

Implementations

impl<T> Var<T>

pub fn env(&self) -> ContractEnv

Returns the contract environment associated with the variable.

impl<T: FromBytes> Var<T>

pub fn get(&self) -> Option<T>

Retrieves the value of the variable.

Returns Some(value) if the variable has a value, or None if it is unset.

pub fn get_or_revert_with<E: Into<OdraError>>(&self, error: E) -> T

Retrieves the value of the variable or reverts with an error.

If the variable has a value, it is returned. Otherwise, the provided error is reverted.

impl<T: FromBytes + Default> Var<T>

pub fn get_or_default(&self) -> T

Returns the value of the variable, or the default value of the type if the variable is None.

impl<T: ToBytes + CLTyped> Var<T>

pub fn set(&mut self, value: T)

Sets the value of the variable.

impl<V: ToBytes + FromBytes + CLTyped + OverflowingAdd + Default> Var<V>

pub fn add(&mut self, value: V)

Utility function that gets the current value and adds the passed value and sets the new value to the storage.

If the operation fails due to overflow, the currently executing contract reverts.

impl<V: ToBytes + FromBytes + CLTyped + OverflowingSub + Default> Var<V>

pub fn subtract(&mut self, value: V)

Utility function that gets the current value and subtracts the passed value and sets the new value to the storage.

If the operation fails due to overflow, the currently executing contract reverts.

Trait Implementations

impl<T> ModuleComponent for Var<T>

Implements the ModuleComponent trait for the Var struct.

fn instance(env: Rc<ContractEnv>, index: u8) -> Self

Creates a new instance of Var with the given environment and index.

impl<T> Revertible for Var<T>

fn revert<E: Into<OdraError>>(&self, e: E) -> !

Reverts the contract execution with the given error.

impl<T> ModulePrimitive for Var<T>