Struct Counter

pub struct Counter { /* private fields */ }

Represents counters.

Implementations

impl Counter

pub const DEFAULT: Self

The default Self value.

pub const fn new(value: u64) -> Self

Constructs Self.

pub const fn get(self) -> u64

Returns the value of this counter.

pub const fn try_next(self) -> Option<Self>

Returns the incremented counter while checking for overflows.

Note

Since Counter is Copy, one can continue using the original counter after calling this method. So, even if None is returned, the original counter will not be dropped.

Examples

use otp_std::Counter;

let counter = Counter::new(0);
let expected = Counter::new(1);

assert_eq!(counter.try_next(), Some(expected));

Returning None on overflows:

use otp_std::Counter;

let counter = Counter::new(u64::MAX);

assert_eq!(counter.try_next(), None);

pub const fn next(self) -> Self

Returns the incremented counter, panicking on overflows.

Panics

This method will panic if the counter overflows.

Examples

use otp_std::Counter;

let counter = Counter::new(0);
let expected = Counter::new(1);

assert_eq!(counter.next(), expected);

Panicking on overflows:

use otp_std::Counter;

let counter = Counter::new(u64::MAX);

counter.next();

Trait Implementations

impl Clone for Counter

fn clone(&self) -> Counter

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Counter

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

Formats the value using the given formatter.

impl Default for Counter

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Counter

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Counter

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

Formats the value using the given formatter.

impl From<Counter> for u64

fn from(counter: Counter) -> Self

Converts to this type from the input type.

impl From<u64> for Counter

fn from(value: u64) -> Self

Converts to this type from the input type.

impl FromStr for Counter

type Err = Error

The associated error which can be returned from parsing.

fn from_str(string: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl Hash for Counter

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Counter

fn eq(&self, other: &Counter) -> 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 Counter

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for Counter

impl Eq for Counter

impl StructuralPartialEq for Counter