Struct Rent 

#[repr(C)]
pub struct Rent {
    pub lamports_per_byte: u64,
    pub exemption_threshold: [u8; 8],
    pub burn_percent: u8,
}

Configuration of network rent.

Fields

lamports_per_byte: u64

Rental rate in lamports/byte.

exemption_threshold: [u8; 8]

👎Deprecated since 4.1.0:

Use Rent::minimum_balance() directly

Formerly, the amount of time (in years) a balance must include rent for the account to be rent exempt. Now it’s just empty space.

burn_percent: u8

👎Deprecated since 4.1.0:

Rent no longer exists

Formerly, the percentage of collected rent that is burned.

Implementations

impl Rent

pub fn minimum_balance(&self, data_len: usize) -> u64

Calculates the minimum balance for rent exemption.

This method avoids floating-point operations when the exemption_threshold is the default value.

Arguments

• data_len - The number of bytes in the account

Returns

The minimum balance in lamports for rent exemption.

Panics

Panics if data_len exceeds the maximum permitted data length or if the lamports_per_byte is too large based on the exemption_threshold.

pub fn minimum_balance_unchecked(&self, data_len: usize) -> u64

Calculates the minimum balance for rent exemption without performing any validation.

This method avoids floating-point operations when the exemption_threshold is the default value.

Important

The caller must ensure that data_len is within the permitted limit and the lamports_per_byte is within the permitted limit based on the exemption_threshold to avoid overflow.

Arguments

• data_len - The number of bytes in the account

Returns

The minimum balance in lamports for rent exemption.

pub fn try_minimum_balance(&self, data_len: usize) -> Option<u64>

Calculates the minimum balance for rent exemption.

This method avoids floating-point operations when the exemption_threshold is the default value.

Arguments

• data_len - The number of bytes in the account

Returns

• Some(u64) - The minimum balance in lamports for rent exemption, if all checks pass.
• None - If data_len exceeds the maximum permitted data length, or if the lamports_per_byte is too large based on the exemption_threshold, which would cause an overflow.

pub fn is_exempt(&self, balance: u64, data_len: usize) -> bool

Whether a given balance and data length would be exempt.

pub fn free() -> Rent

Creates a Rent that charges no lamports.

This is used for testing.

pub fn with_lamports_per_byte(lamports_per_byte: u64) -> Rent

Creates a Rent with lamports per byte

Trait Implementations

impl Clone for Rent

fn clone(&self) -> Rent

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Rent

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

Formats the value using the given formatter.

impl Default for Rent

fn default() -> Rent

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Rent

fn deserialize<__D>( __deserializer: __D, ) -> Result<Rent, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl GetSysvar for Rent

fn get() -> Result<Rent, ProgramError>

Load the sysvar directly from the runtime.

impl PartialEq for Rent

fn eq(&self, other: &Rent) -> 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 Serialize for Rent

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Rent

impl Sysvar for Rent

fn get() -> Result<Rent, ProgramError>

Load the sysvar directly from the runtime.

impl SysvarId for Rent

fn id() -> Address

The Address of the sysvar.

fn check_id(address: &Address) -> bool

Returns true if the given address is the ID.

impl SysvarSerialize for Rent

Available on crate feature bincode only.

fn size_of() -> usize

The size in bytes of the sysvar as serialized account data.

fn from_account_info( account_info: &AccountInfo<'_>, ) -> Result<Self, ProgramError>

Deserializes the sysvar from its AccountInfo.

fn to_account_info(&self, account_info: &mut AccountInfo<'_>) -> Option<()>

Serializes the sysvar to AccountInfo.