Enum ScalarExpr 

pub enum ScalarExpr {
    Const(Span<u64>),
    SymbolAccess(SymbolAccess),
    BoundedSymbolAccess(BoundedSymbolAccess),
    Binary(BinaryExpr),
    Call(Call),
    Let(Box<Let>),
    BusOperation(BusOperation),
    Null(Span<()>),
    Unconstrained(Span<()>),
}

Scalar expressions are expressions which evaluate to a single scalar value, i.e. they have no vector or matrix elements. Only scalar expressions are valid in a constraint statement.

Variants

Const(Span<u64>)

A constant scalar value, i.e. integer

SymbolAccess(SymbolAccess)

A reference to a named value

NOTE: Symbol accesses in a ScalarExpr context must produce scalar values.

BoundedSymbolAccess(BoundedSymbolAccess)

A reference to a trace column on a particular boundary of the trace, which must produce a scalar

NOTE: This is only a valid expression in boundary constraints

Binary(BinaryExpr)

A binary operator over scalar values

Call(Call)

A call to a pure function or evaluator

NOTE: This is only a valid scalar expression when one of the following hold:

1. The call is the top-level expression of a constraint, and is to an evaluator function
2. The call is not the top-level expression of a constraint, and is to a pure function that produces a scalar value type.

If neither of the above are true, the call is invalid in a ScalarExpr context

Let(Box<Let>)

An expression that binds a local variable to a temporary value during evaluation.

NOTE: This is only a valid scalar expression during the inlining phase, when we expand binary expressions or function calls to a block of statements, and only when the result of evaluating the let produces a valid scalar expression.

BusOperation(BusOperation)

A bus operation

Null(Span<()>)

An empty bus

Unconstrained(Span<()>)

An unconstrained bus

Implementations

impl ScalarExpr

pub fn is_constant(&self) -> bool

Returns true if this is a constant value

pub fn has_block_like_expansion(&self) -> bool

Returns true if this scalar expression could expand to a block, e.g. due to a function call being inlined.

pub fn ty(&self) -> Result<Option<Type>, SourceSpan>

Returns the resolved type of this expression, if known.

Returns Ok(Some) if the type could be resolved without conflict. Returns Ok(None) if type information was missing. Returns Err if the type could not be resolved due to a conflict, with a span covering the source of the conflict.

Trait Implementations

impl Clone for ScalarExpr

fn clone(&self) -> ScalarExpr

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ScalarExpr

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

Formats the value using the given formatter.

impl Display for ScalarExpr

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

Formats the value using the given formatter.

impl From<u64> for ScalarExpr

fn from(value: u64) -> Self

Converts to this type from the input type.

impl PartialEq for ScalarExpr

fn eq(&self, other: &ScalarExpr) -> 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 Spanned for ScalarExpr

fn span(&self) -> SourceSpan

impl TryFrom<Expr> for ScalarExpr

type Error = InvalidExprError

The type returned in the event of a conversion error.

fn try_from(expr: Expr) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<ScalarExpr> for Expr

type Error = InvalidExprError

The type returned in the event of a conversion error.

fn try_from(expr: ScalarExpr) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<ScalarExpr> for Statement

type Error = ()

The type returned in the event of a conversion error.

fn try_from(expr: ScalarExpr) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<Statement> for ScalarExpr

type Error = InvalidExprError

The type returned in the event of a conversion error.

fn try_from(stmt: Statement) -> Result<Self, Self::Error>

Performs the conversion.

impl Eq for ScalarExpr

impl StructuralPartialEq for ScalarExpr