Enum phreak_facts::Value

pub enum Value {
    Integer(i64),
    Uuid(Uuid),
    DateTime(DateTime<Utc>),
    String(String),
}

Wrapper for values of different types

Variants

Integer(i64)

Uuid(Uuid)

DateTime(DateTime<Utc>)

String(String)

Implementations

impl Value

pub fn new() -> Self

Create a Value containing the empty string

pub fn describe(&self) -> &str

Returns the type-name of the Value

assert_eq!(Value::from("text").describe(), "string");
assert_eq!(Value::from(42).describe(), "integer");

pub fn typed_cmp(&self, other: &Self) -> Option<Ordering>

Compare function that doesn't convert types, but only compares compatible types, resulting in a Partial Ordening

The standard ordening of Value, as implemented by PartialOrd and Ord performs ordering based on type-order as to meet the strict requirements imposed by Hash and BTree datatypes. This is not the desired behavior for comparing in the Phreak network, so we provide a type-aware alternative.

for PartialOrd the following holds Int.cmp(Str) == Some(Ordering::Less), or Integer < String, while Int.typed_cmp(Str) == None, so no ordering between types.

// compare different numeric types
assert_eq!(Value::from(15u8).typed_cmp( &Value::from(15i32) ), Some(Ordering::Equal));
assert_eq!(Value::from(15u8).typed_cmp( &Value::from(5i32) ), Some(Ordering::Greater));
assert_eq!(Value::from(8u8).typed_cmp( &Value::from(15i32) ), Some(Ordering::Less));

let t = String::from("text");

// compare &str and String
assert_eq!(Value::from("text").typed_cmp( &Value::from(t) ), Some(Ordering::Equal));
assert_eq!(Value::from("b").typed_cmp( &Value::from("a") ), Some(Ordering::Greater));

// can't compare strings and integers
assert_eq!(Value::from("5").typed_cmp( &Value::from(5u8) ), None);
// or string and uuid
assert_eq!(Value::from("5").typed_cmp( &Value::from(Uuid::new_v4()) ), None);
// or uuid and integers
assert_eq!(Value::from(Uuid::new_v4()).typed_cmp( &Value::from(5u8) ), None);

// whereas partial_cmp and cmp succeed (strings come after integers in our storage)
assert_eq!(Value::from("5").partial_cmp( &Value::from(5u8) ), Some(Ordering::Greater));
assert_eq!(Value::from("5").cmp( &Value::from(5u8) ), Ordering::Greater);

pub fn typed_eq(&self, other: &Self) -> bool

Equality function that doesn't convert types, but checks the type of the value.

The standard equality of Value, as implemented by PartialEq and Eq does type conversions in order to meet the strict requirements imposed by Hash and BTree datatypes. This is not the desired behavior for equality in the Phreak network, so we provide a type-aware alternative.

// compare different numeric types
assert_eq!(Value::from(15u8).typed_eq( &Value::from(15i32) ), true);
assert_eq!(Value::from(15u8).typed_eq( &Value::from(5i32) ), false);

// compare int and &str
assert_eq!(Value::from(8).typed_eq( &Value::from("8") ), false);

// compare &str and String
assert_eq!(Value::from("8").typed_eq( &Value::from("8".to_string()) ), true);

Trait Implementations

impl Clone for Value

fn clone(&self) -> Value

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Value

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

Formats the value using the given formatter.

impl Default for Value

fn default() -> Self

Returns the "default value" for a type.

impl<'de> Deserialize<'de> for Value

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

Deserialize this value from the given Serde deserializer.

impl Display for Value

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

Formats the value using the given formatter.

impl Eq for Value

impl<'_> From<&'_ str> for Value

fn from(s: &str) -> Self

Performs the conversion.

impl<T: TimeZone> From<DateTime<T>> for Value

fn from(v: DateTime<T>) -> Self

Performs the conversion.

impl From<String> for Value

fn from(s: String) -> Self

Performs the conversion.

impl From<Uuid> for Value

fn from(v: Uuid) -> Self

Performs the conversion.

impl From<i16> for Value

fn from(v: i16) -> Self

Performs the conversion.

impl From<i32> for Value

fn from(v: i32) -> Self

Performs the conversion.

impl From<i64> for Value

fn from(v: i64) -> Self

Performs the conversion.

impl From<i8> for Value

fn from(v: i8) -> Self

Performs the conversion.

impl From<u16> for Value

fn from(v: u16) -> Self

Performs the conversion.

impl From<u32> for Value

fn from(v: u32) -> Self

Performs the conversion.

impl From<u8> for Value

fn from(v: u8) -> Self

Performs the conversion.

impl Hash for Value

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, 

Feeds a slice of this type into the given [Hasher].

impl Ord for Value

fn cmp(&self, other: &Self) -> Ordering

This method returns an [Ordering] between self and other.

#[must_use]fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl PartialEq<Value> for Value

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

This method tests for self and other values to be equal, and is used by ==.

#[must_use]fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialOrd<Value> for Value

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use]fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for Value

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

Serialize this value into the given Serde serializer.