Struct TransactionFee 

pub struct TransactionFee { /* private fields */ }

The inputs from which a transaction’s fee is computed, mirroring the transaction kernel’s compute_fee procedure.

This is the single Rust implementation of the kernel fee formula: keep it in sync with compute_fee in asm/kernels/transaction-core/src/tx.masm. The kernel’s output-notes fee term is currently hardcoded to zero and thus omitted here.

Implementations

impl TransactionFee

pub fn new(total_cycles: u32) -> Result<Self, TransactionFeeError>

Creates the fee inputs for a transaction executing total_cycles VM cycles.

Mirrors the kernel’s compute_fee: the number of charged verification cycles is ilog2(total_cycles) + 1, where the unconditional + 1 rounds the proof-verification cost up to the next power of two.

Returns an error if total_cycles is 0 (every transaction executes at least the kernel prologue, so a zero cycle count cannot describe a transaction) or exceeds MAX_TX_EXECUTION_CYCLES, the bound the kernel’s compute_fee enforces.

pub fn log_verification_cycles(&self) -> u32

Returns the number of verification cycles the fee is charged for - a logarithmic measure of the transaction’s total cycle count, not an exact cycle count.

pub fn with_safety_margin(self, extra_verification_cycles: u32) -> Self

Returns fee inputs charging extra_verification_cycles on top of the formula’s verification cycles, e.g. as a safety margin when the fee is derived from an estimated rather than a measured cycle count.

The addition saturates at u32::MAX verification cycles; a fee that large is rejected by Self::compute_fee for any base fee above 2^31.

pub fn compute_fee( &self, fee_parameters: &FeeParameters, ) -> Result<AssetAmount, TransactionFeeError>

Computes the fee under the given fee parameters.

Returns an error if the fee exceeds AssetAmount::MAX: the formula’s own verification cycles keep the fee far below it, but a large Self::with_safety_margin can push it beyond.

Trait Implementations

impl Clone for TransactionFee

fn clone(&self) -> TransactionFee

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for TransactionFee

impl Debug for TransactionFee

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

Formats the value using the given formatter.

impl Eq for TransactionFee

impl PartialEq for TransactionFee

fn eq(&self, other: &TransactionFee) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for TransactionFee