Enum Pattern 

pub enum Pattern {
    Wildcard {
        name: String,
        constraints: Option<WildcardConstraints>,
    },
    Exact(Expression),
    Add(Vec<Pattern>),
    Mul(Vec<Pattern>),
    Pow(Box<Pattern>, Box<Pattern>),
    Function {
        name: String,
        args: Vec<Pattern>,
    },
}

A pattern that can match against expressions

Patterns support wildcards and structural matching to enable transformation rules and equation manipulation.

Variants

Wildcard

Match any expression and bind to a name, optionally with constraints

Fields

name: String

constraints: Option<WildcardConstraints>

Exact(Expression)

Match a specific expression exactly

Add(Vec<Pattern>)

Match addition with pattern terms (supports commutative matching)

Mul(Vec<Pattern>)

Match multiplication with pattern factors (supports commutative matching)

Pow(Box<Pattern>, Box<Pattern>)

Match power with pattern base and exponent

Function

Match function call with pattern arguments

Fields

name: String

args: Vec<Pattern>

Implementations

impl Pattern

pub fn wildcard(name: impl Into<String>) -> Self

Create a simple wildcard pattern without constraints

pub fn wildcard_excluding( name: impl Into<String>, exclude: Vec<Expression>, ) -> Self

Create a wildcard pattern with exclude constraints

pub fn wildcard_with_properties( name: impl Into<String>, properties: Vec<fn(&Expression) -> bool>, ) -> Self

Create a wildcard pattern with property constraints

Trait Implementations

impl Clone for Pattern

fn clone(&self) -> Pattern

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Pattern

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

Formats the value using the given formatter.

impl PartialEq for Pattern

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