Trait CostType

pub trait CostType:
    Sized
    + From<usize>
    + Copy
    + Send
    + Mul<Output = Self>
    + Div<Output = Self>
    + Add<Output = Self>
    + Sub<Output = Self>
    + Shr<usize, Output = Self>
    + Shl<usize, Output = Self>
    + AddAssign
    + SubAssign
    + Ord
    + Debug {
    // Required methods
    fn as_u256(&self) -> U256;
    fn from_u256(val: U256) -> Result<Self>;
    fn as_usize(&self) -> usize;
    fn overflow_add(self, other: Self) -> (Self, bool);
    fn overflow_mul(self, other: Self) -> (Self, bool);
    fn overflow_mul_shr(self, other: Self, shr: usize) -> (Self, bool);
}

Cost calculation type. For low-gas usage we calculate costs using usize instead of U256

Required Methods

fn as_u256(&self) -> U256

Converts this cost into U256

fn from_u256(val: U256) -> Result<Self>

Tries to fit U256 into this Cost type

fn as_usize(&self) -> usize

Convert to usize (may panic)

fn overflow_add(self, other: Self) -> (Self, bool)

Add with overflow

fn overflow_mul(self, other: Self) -> (Self, bool)

Multiple with overflow

fn overflow_mul_shr(self, other: Self, shr: usize) -> (Self, bool)

Single-step full multiplication and shift: (self*other) >> shr Should not overflow on intermediate steps

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl CostType for usize

fn as_u256(&self) -> U256

fn from_u256(val: U256) -> Result<Self>

fn as_usize(&self) -> usize

fn overflow_add(self, other: Self) -> (Self, bool)

fn overflow_mul(self, other: Self) -> (Self, bool)

fn overflow_mul_shr(self, other: Self, shr: usize) -> (Self, bool)

impl CostType for U256

fn as_u256(&self) -> U256

fn from_u256(val: U256) -> Result<Self>

fn as_usize(&self) -> usize

fn overflow_add(self, other: Self) -> (Self, bool)

fn overflow_mul(self, other: Self) -> (Self, bool)

fn overflow_mul_shr(self, other: Self, shr: usize) -> (Self, bool)

Implementors