Struct Model

pub struct Model {
    pub variables: HashMap<Name, DecisionVariable>,
    pub constraints: Expression,
    pub context: Arc<RwLock<Context<'static>>>,
    /* private fields */
}

Represents a computational model containing variables, constraints, and a shared context.

The Model struct holds a set of variables and constraints for manipulating and evaluating symbolic expressions.

Fields

• variables:

  • Type: SymbolTable
  • A table that links each variable’s name to its corresponding DecisionVariable.
  • For example, the name x might be linked to a DecisionVariable that says x can only take values between 1 and 10.

• constraints:

  • Type: Expression
  • Represents the logical constraints applied to the model’s variables.
  • Can be a single constraint or a combination of various expressions, such as logical operations (e.g., AND, OR), arithmetic operations (e.g., SafeDiv, UnsafeDiv), or specialized constraints like SumEq.

• context:

  • Type: Arc<RwLock<Context<'static>>>
  • A shared object that stores global settings and state for the model.
  • Can be safely read or changed by multiple parts of the program at the same time, making it good for multi-threaded use.

• next_var:

  • Type: RefCell<i32>
  • A counter used to create new, unique variable names.
  • Allows updating the counter inside the model without making the whole model mutable.

Usage

This struct is typically used to:

• Define a set of variables and constraints for rule-based evaluation.
• Have transformations, optimizations, and simplifications applied to it using a set of rules.

Fields

variables: HashMap<Name, DecisionVariable>

constraints: Expression

context: Arc<RwLock<Context<'static>>>

Implementations

impl Model

pub fn new( variables: HashMap<Name, DecisionVariable>, constraints: Expression, context: Arc<RwLock<Context<'static>>>, ) -> Model

pub fn new_empty(context: Arc<RwLock<Context<'static>>>) -> Model

pub fn update_domain(&mut self, name: &Name, new_domain: Domain)

pub fn get_domain(&self, name: &Name) -> Option<&Domain>

pub fn add_variable(&mut self, name: Name, decision_var: DecisionVariable)

pub fn get_constraints_vec(&self) -> Vec<Expression>

pub fn set_constraints(&mut self, constraints: Vec<Expression>)

pub fn set_context(&mut self, context: Arc<RwLock<Context<'static>>>)

pub fn add_constraint(&mut self, expression: Expression)

pub fn add_constraints(&mut self, expressions: Vec<Expression>)

pub fn gensym(&self) -> Name

Returns an arbitrary variable name that is not in the model.

Trait Implementations

impl Clone for Model

fn clone(&self) -> Model

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Model

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Model

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Model

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

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for Model