Enum Value

pub enum Value {
    Integer(i64),
    Float(f64),
    Boolean(bool),
    String(String),
    Function(Function),
    Null,
}

The Value enum represents a data type that can be stored in an Environment. Each type contains the data it represents (e.g. a Value::Integer contains an i64).

There are 6 types of values: Integer, Float, Boolean, String, Function and Null.

Variants

Integer(i64)

Float(f64)

Boolean(bool)

String(String)

Function(Function)

Null

The Null variant is used to represent the absence of a value. It is used to represent the result of an expression that doesn’t return anything (e.g. a function call that doesn’t return anything).

Implementations

impl Value

pub fn variant_name(&self) -> &'static str

Returns the display name of the variant of the Value enum.

pub fn cast_to_boolean(&self) -> Result<Self, Error>

This method converts any Value to a Value::Boolean. It returns an error if the conversion is not possible.

pub fn cast_to_string(&self) -> Self

This method converts any Value to a Value::Integer. It returns an error if the conversion is not possible. (For now, all conversions are possible.)

pub fn eq(&self, other: &Self) -> Result<Self, Error>

pub fn ne(&self, other: &Self) -> Result<Self, Error>

pub fn lt(&self, other: &Self) -> Result<Self, Error>

pub fn le(&self, other: &Self) -> Result<Self, Error>

pub fn gt(&self, other: &Self) -> Result<Self, Error>

pub fn ge(&self, other: &Self) -> Result<Self, Error>

pub fn not(&self) -> Result<Self, Error>

This method returns the logical negation of a Value::Boolean. It returns an error for all other types.

pub fn and(&self, other: &Self) -> Result<Self, Error>

This method returns the logical and of two Value::Booleans. It returns an error for all other types.

pub fn or(&self, other: &Self) -> Result<Self, Error>

This method returns the logical or of two Value::Booleans. It returns an error for all other types.

pub fn sub(&self, other: &Self) -> Result<Self, Error>

pub fn mul(&self, other: &Self) -> Result<Self, Error>

pub fn rem(&self, other: &Self) -> Result<Self, Error>

pub fn add(&self, other: &Self) -> Result<Self, Error>

This method returns the sum of two Values. It returns an error if the operation is not possible.

pub fn div(&self, other: &Self) -> Result<Self, Error>

This method returns the result of dividing two Values. It returns an error if the operation is not possible, or if a division by zero occurs.

pub fn neg(&self) -> Result<Self, Error>

This method returns the negation of a Value. It returns an error if the operation is not possible.

Trait Implementations

impl Debug for Value

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

Formats the value using the given formatter.

impl Display for Value

Implementing the Display trait for Value allows for the pretty printing of values.

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

Formats the value using the given formatter.

impl PartialEq for Value

fn eq(&self, other: &Value) -> 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 StructuralPartialEq for Value