Trait ReduceRule 

pub trait ReduceRule<V: VTable, C: RewriteContext>:
    Debug
    + Send
    + Sync
    + 'static {
    // Required method
    fn reduce(
        &self,
        expr: &ExpressionView<'_, V>,
        ctx: &C,
    ) -> VortexResult<Option<Expression>>;
}

A rewrite rule that transforms expressions without needing context.

Called during bottom-up traversal after children have been processed. This is useful for self-contained rewrites like: select(...) -> pack(get_item(...))

Type Parameters

• V - The VTable type this rule applies to. The rule will only be invoked for expressions with this vtable type, providing compile-time type safety.

Required Methods

fn reduce( &self, expr: &ExpressionView<'_, V>, ctx: &C, ) -> VortexResult<Option<Expression>>

Try to rewrite an expression.

Arguments

• expr - The expression to potentially rewrite (already downcast to type V)
• ctx - Context for the rewrite (dtype, etc.)

Returns

• Some(new_expr) if the rule applies and produces a rewritten expression
• None if the rule does not apply

Implementors