Struct ConstraintSystem 

pub struct ConstraintSystem<F: TowerField> { /* private fields */ }

Builder context for algebraic constraints.

Implementations

impl<F: TowerField> ConstraintSystem<F>

pub fn new() -> Self

Create a new constraint system.

pub fn from_ast(ast: ConstraintAst<F>) -> Self

Create a builder from an existing AST.

pub fn col(&self, idx: usize) -> Expr<'_, F>

Reference to a column in the current row.

pub fn next(&self, idx: usize) -> Expr<'_, F>

Reference to a column in the next row.

pub fn constant(&self, val: F) -> Expr<'_, F>

Field constant.

pub fn one(&self) -> Expr<'_, F>

The multiplicative identity.

pub fn scale(&self, coeff: F, expr: Expr<'_, F>) -> Expr<'_, F>

Scalar multiplication: coeff * expr.

Use this for powers of 2, coefficients, etc. Orphan rules prevent implementing F * Expr via operator overloading.

pub fn sum(&self, children: &[Expr<'_, F>]) -> Expr<'_, F>

N-ary sum. More efficient than chaining binary + for linear combinations (avoids deep Add chains).

pub fn constrain(&self, expr: Expr<'_, F>)

Register a constraint: expr = 0.

The expression must evaluate to zero for every valid row in the execution trace.

pub fn constrain_named(&self, label: &'static str, expr: Expr<'_, F>)

pub fn assert_boolean(&self, s: Expr<'_, F>)

Assert that s is boolean: s * (s + 1) = 0.

In GF(2^k), s + 1 equals s - 1. Enforces s ∈ {0, 1}.

pub fn assert_zero_when(&self, sel: Expr<'_, F>, body: Expr<'_, F>)

Assert that body = 0 whenever sel = 1.

Registers sel * body = 0. When sel = 0, the constraint is trivially satisfied.

pub fn assert_one_hot(&self, selectors: &[Expr<'_, F>])

Assert that exactly one selector is active. Enforces: sum(selectors) = 1.

In GF(2^k): sum(s_i) + 1 = 0.

pub fn assert_paired_bus_mutex(&self, s_send: usize, s_recv: usize)

Emit the s_send · s_recv = 0 mutex root plus boolean checks on both selectors.

pub fn build(self) -> ConstraintAst<F>

Consume the builder and produce a ConstraintAst.

All Expr handles must be dropped before calling this (enforced by the borrow checker, build takes self).

Trait Implementations

impl<F: TowerField> Default for ConstraintSystem<F>

fn default() -> Self

Returns the “default value” for a type.